• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

A Few Hypothetical Questions.

Stickleback

Member
Joined
12 Nov 2009
Messages
189
Location
Vietnam
A few musings...

What would happen if you dosed a low tech tank with high tech levels of CO2?

What would happen if you didn't do any water changes on a High tech, EI tank?

Why don't rivers have more algae, considering the high light levels, surface agitation and lack of CO2 injection?

A shallow british river in full summer sun is roughly what WPG equivalent?
 
1. the plants would really appreciate it. light is a driving factor not co2, so as long as you dont go crazy, like more than 40ppm of co2 then it will make no difference.

2. the ferts you add in EI are to keep you in a ballpark range, the water changes are to reset these values. so without water changes the ferts that are not used up will build and build until you have a brackish water setup. this will very quickly become toxic to plants and fish. excess nutrients cause issues just like too little.

3. co2 does not kill or inhibit algae. the large surface area of rivers, the moving water etc. is where the majority of the dissolved co2 comes from. rivers also have a much more complete eco system, from insects, crustaceans, molluscs, fish, bacteria etc. that all use algae as a primary food source. compared to the volume of water there is also very little nutrients for algae to grow. some algae also do not like flow, so will not grow steadily in a river.

4. the earth receives ~1300-1500 w/m2 so imagine ten 150w mh over a 1m by 1m tank.
 
wearsbunnyslippers said:
1. the plants would really appreciate it. light is a driving factor not co2, so as long as you dont go crazy, like more than 40ppm of co2 then it will make no difference.
This is not really true. You can go as crazy as you want. The limiting factor is only ever the comfort and safety of the fauna, not the plants. It should be pointed out that adding CO2 to a low tech tank immediately makes it a high tech tank. High tech tanks are by definition CO2 injected tanks.

wearsbunnyslippers said:
2. the ferts you add in EI are to keep you in a ballpark range, the water changes are to reset these values. so without water changes the ferts that are not used up will build and build until you have a brackish water setup. this will very quickly become toxic to plants and fish. excess nutrients cause issues just like too little.
This isn't very accurate either. If the only reason you were doing a water change was to control the buildup of nutrients then all you would have to do is to stop dosing for a period of time and allow the nutrient levels to fall before resuming the dosing. If this were the case then EI dosing would look substantially different i.e, dose for one week and then don't dose for one week, then resume dosing for one week. You don't need to do a water change to control nutrient buildup.

The fundamental reason for doing a water change is to clean the tank of toxic substances produced by the accelerated metabolism of plants due to their uptake of CO2 and nutrients. These waste products are not only toxic, but they encourage algae as they biodegrade. Not cleaning an EI tank encourages algae due to the excess dirt and organic waste. It also encourages poor fish health. The fact that changing the water also "resets" the nutrient levels is merely a coincidence some find convenient.

Cheers,
 
1. the plants would really appreciate it. light is a driving factor not co2, so as long as you dont go crazy, like more than 40ppm of co2 then it will make no difference.

The first statement is true 'The plants will really appreciate it' but the last one 'it will make no difference' isn't.

If you have a lo-tec setup say 0.9wpg ;) and then add CO2 (as Ceg says becoming a hi-tec tank) you will see an almost immediate difference. Growth speed will increase substantially without adding any more light. In effect a lo-tec tank is forcing the plants to grow slower due to CO2 limitation. When you add the CO2 you remove the limitation and the plant then uses the energy it saves (not having to work hard for CO2) to utilise the light available more efficiently.

AC
 
ceg4048 said:
The fundamental reason for doing a water change is to clean the tank of toxic substances produced by the accelerated metabolism of plants due to their uptake of CO2 and nutrients. These waste products are not only toxic, but they encourage algae as they biodegrade. Not cleaning an EI tank encourages algae due to the excess dirt and organic waste. It also encourages poor fish health. The fact that changing the water also "resets" the nutrient levels is merely a coincidence some find convenient.

Cheers,

ceg4048

Out of interest what are the toxic substances released by plants? I might be wrong but I seem to remember you arguing that the reason for water changes was to dilute algal spores?
 
SuperColey1 said:
1. the plants would really appreciate it. light is a driving factor not co2, so as long as you dont go crazy, like more than 40ppm of co2 then it will make no difference.

The first statement is true 'The plants will really appreciate it' but the last one 'it will make no difference' isn't.

If you have a lo-tec setup say 0.9wpg ;) and then add CO2 (as Ceg says becoming a hi-tec tank) you will see an almost immediate difference. Growth speed will increase substantially without adding any more light. In effect a lo-tec tank is forcing the plants to grow slower due to CO2 limitation. When you add the CO2 you remove the limitation and the plant then uses the energy it saves (not having to work hard for CO2) to utilise the light available more efficiently.

AC

In that case, supposing you were keeping to the low tech dosing regime, they would then become nutrient limited. You would therefore expect to see algae?

R
 
Stickleback said:
In that case, supposing you were keeping to the low tech dosing regime, they would then become nutrient limited. You would therefore expect to see algae?R

Yes indeed ;) You have to provide enough 'food' for the plants. C is a nutrient just as NPK+traces are. They use the nitrate/nitrite/ammonia to get nitrogen. They use the CO2 to get carbon. By limiting CO2 you are technically limiting nutrients however I can't explain why it doesn't work with the other nutrients (NPK.) Limiting the other nutrients means algae fest in most cases!!!

AC
 
Brenmuk said:
ceg4048 said:
The fundamental reason for doing a water change is to clean the tank of toxic substances produced by the accelerated metabolism of plants due to their uptake of CO2 and nutrients. These waste products are not only toxic, but they encourage algae as they biodegrade. Not cleaning an EI tank encourages algae due to the excess dirt and organic waste. It also encourages poor fish health. The fact that changing the water also "resets" the nutrient levels is merely a coincidence some find convenient.

Cheers,

ceg4048

Out of interest what are the toxic substances released by plants? I might be wrong but I seem to remember you arguing that the reason for water changes was to dilute algal spores?
Hi Bremuk,
While getting rid of spores is one of the arguments, it isn't a primary one for a stable tank. Multiple water changes that delete spores is one of the techniques used when one is addressing an algal bloom. Vegetative algae produce spores in abundance, which then bloom and produce more spores. If the tank is suffering a bloom then that means the trigger mechanism has been activated so that needs to be addressed. Clearing the tank of as many spores as possible helps reduce the quantity and severity of the bloom. Under normal, stable conditions we don't really pay too much attention to the level of spores because it's relatively low anyway and as long as they stay as spores it's not a big deal.

The proteins, amino acids, fats and carbohydrates that are expelled from the plants during accelerated metabolism become problematic in the confines of the tank. They become part of the biofilm and block access to nutrients/CO2. These products also decay, lowering the oxygen content which have an impact on fauna. The ammonia loading rate is affected in the decay process and the spores of some algal species use this rate as a trigger mechanism. People don't realize how important it is to have a clean tank. When a tank is being setup, there is not enough of these products and so the tank becomes unstable, which triggers algae. When the tank is mature then we have too much of these products which can trigger algae. So yes, absolutely we want to get spores out of the tank with water changes, but fundamentally we want to use the water change to clean the gunk off the surface of the plants, clean the water column of organic pollution and to unload the sediment of built up debris and detritus. People are so freaked out about nutrients that they miss the boat entirely. In a fuel injected tank, keeping it meticulously clean will be the best possible thing you can do for plants and fish.

While the microbes that perform nitrification do appreciate the products expelled from the plant, the buildup is too much for the plants and animals themselves. With non-CO2 / lean dosing programs, since the nutrient uptake is much slower, the expulsion rate of organic waste is also much slower. The plants adapt to the low nutrient/CO2 rate, become leaner and much more efficient, reducing the waste expulsion even further. It's a much more stable approach as long as the lighting level is not excessive. Enriching CO2 automatically sends the tank into the passing lane of The Autobahn.

Stickleback said:
In that case, supposing you were keeping to the low tech dosing regime, they would then become nutrient limited. You would therefore expect to see algae?
As Andy notes, since carbon enrichment defines low tech/high tech then a low tech tank is basically CO2 limited. The CO2 limiting occurs faster than NPK limiting, but even low tech tanks can suffer NPK limiting. But this is easy to fix with fish in the tank. Adding small amounts of inorganic salts, either to water column (weekly or bi-weekly) or to the sediment allows faster uptake and better health. Healthy plants will resist algal attacks, so no, one does not necessarily "expect" to see algae in a low tech environment.

Cheers,
 
ceg4048 said:
This is not really true. You can go as crazy as you want. The limiting factor is only ever the comfort and safety of the fauna, not the plants. It should be pointed out that adding CO2 to a low tech tank immediately makes it a high tech tank. High tech tanks are by definition CO2 injected tanks.

i have seen some of the CAU guys dosing up to 40ppm without issues, of course you have to be really on the ball to make sure you are on top of things, as the slightest mistake at these levels can be dangerous to the fauna. if it is a traditional low tech setup the lighting wont be very high, so going higher than 40ppm will just be wasting gas, the plants wont be able to utilise it all.

ceg4048 said:
This isn't very accurate either. If the only reason you were doing a water change was to control the buildup of nutrients then all you would have to do is to stop dosing for a period of time and allow the nutrient levels to fall before resuming the dosing. If this were the case then EI dosing would look substantially different i.e, dose for one week and then don't dose for one week, then resume dosing for one week. You don't need to do a water change to control nutrient buildup.

The fundamental reason for doing a water change is to clean the tank of toxic substances produced by the accelerated metabolism of plants due to their uptake of CO2 and nutrients. These waste products are not only toxic, but they encourage algae as they biodegrade. Not cleaning an EI tank encourages algae due to the excess dirt and organic waste. It also encourages poor fish health. The fact that changing the water also "resets" the nutrient levels is merely a coincidence some find convenient.

Cheers,

if this was really the case, why then in el natural and tom's low tech setup methods, do they recommend little to no water changes, no matter how much plant mass you have producing toxic substances? plants normally store there toxins and metabolic wastes in their leaves, and when they reach a certain point the leaf dies. as long as you are not letting loads of dead plant matter collect in your tank, i dont see how there will be any plant toxin buildup...

SuperColey1 said:
1. the plants would really appreciate it. light is a driving factor not co2, so as long as you dont go crazy, like more than 40ppm of co2 then it will make no difference.

The first statement is true 'The plants will really appreciate it' but the last one 'it will make no difference' isn't.

If you have a lo-tec setup say 0.9wpg ;) and then add CO2 (as Ceg says becoming a hi-tec tank) you will see an almost immediate difference. Growth speed will increase substantially without adding any more light. In effect a lo-tec tank is forcing the plants to grow slower due to CO2 limitation. When you add the CO2 you remove the limitation and the plant then uses the energy it saves (not having to work hard for CO2) to utilise the light available more efficiently.

AC

yes, but the plants can only grow so fast without increasing the light and nutrients, they will grow better, thats why i said the plants would appreciate it, but only up to a point. the second statement pertained to going higher than 40ppm in a lowtech setup and this would just be wasting co2 and make no difference..
 
wearsbunnyslippers said:
i have seen some of the CAU guys dosing up to 40ppm without issues, of course you have to be really on the ball to make sure you are on top of things, as the slightest mistake at these levels can be dangerous to the fauna. if it is a traditional low tech setup the lighting wont be very high, so going higher than 40ppm will just be wasting gas, the plants wont be able to utilise it all.

The plants won't be able to utilise it all, after all there are suggestions that as much as 95% of the injected CO2 is lost and never sees a plant. I used to be in the region of 35ppm on my tank (0.9WPG) with no problems. However I had 3 DCs in different positions and plenty of fish to tell me if it was too high :)

At the end of the day if we were so worried about wasting gas we wouldn't go the injection route!!! After all I had my water surface turbulent to bring in more O and thus was wasting even more that way too.

Do plants really store all their toxins in their leaves and then those leaves die? Does that mean that leaves in my tank that are quite literally years old are full of waste? May sound like i'm being a little finickity. Just the first time I heard about this.

yes, but the plants can only grow so fast without increasing the light and nutrients, they will grow better, thats why i said the plants would appreciate it, but only up to a point. the second statement pertained to going higher than 40ppm in a lowtech setup and this would just be wasting co2 and make no difference..

Indeed. The plants with low light and no CO2 will grow at a very slow place. In most cases so slow that it takes photos months apart to see the difference. Add CO2 you can see the growth without the pictures. You remember last week and this week is already more. 10-20x according to TB. Improve the light (adding more light does not necessarily mean the light is improved) then of course the plants are going to be driven even faster. How much faster? I would suggest the improvement from adding CO2 to a previously lo-tec low light tank will be a higher ratio of improvement than increasing light on a hi tec tank. Pure speculation on my part but there you go :)

AC
 
wearsbunnyslippers said:
if this was really the case, why then in el natural and tom's low tech setup methods, do they recommend little to no water changes, no matter how much plant mass you have producing toxic substances? plants normally store there toxins and metabolic wastes in their leaves, and when they reach a certain point the leaf dies. as long as you are not letting loads of dead plant matter collect in your tank, i dont see how there will be any plant toxin buildup...

Because in EI natural tanks you dont inject CO2. You rely on natural CO2 from respiring fish (and plants for that matter). An equilibrium is therefore reached. Doing a water change with tap water (which would contain much higher levels of dissolved CO2) would dramatically change the CO2 conc which the plants had gotten used to. The CO2 is unstable therefore you'll most likley get algae. So, the water changes are not advised. Well...maybe 3 a year.
As a result of EI natural tanks not having injecting CO2, the plant growth isnt anywhere near as quick therefore the toxic substances produced by the accelerated metabolism of the plants isn't anywhere near as high. So it poses no threat. So water changes are needed as much at all.
 
@SuperColey1 - so why are we arguing, i agree 100% that adding co2 will be beneficial, but up to a point, adding more co2 after that is just wasting, we both saying the same thing :p

SuperColey1 said:
Do plants really store all their toxins in their leaves and then those leaves die? Does that mean that leaves in my tank that are quite literally years old are full of waste? May sound like i'm being a little finickity. Just the first time I heard about this.

AC

name one plant in your tank thats leaves are literally years old? not stems or rhizomes, leaves...

maybe some extremely slow growing anubias or crypts, and if they are really that slow growing, there is no way the leaves have reached their saturation levels yet, when they do, they will yellow and die.

Wikipedia said:
source

In plants, breakdown of substances is much slower than in animals. Hence accumulation of waste is much slower and there are no special organs of excretion. Green plants in darkness or plants that do not contain chlorophyll produce carbon dioxide and water as respiratory waste products. Carbon dioxide released during respiration gets utilized during photosynthesis.Oxygen itself can be thought of as a waste product generated during photosynthesis. Plants can get rid of excess water by transpiration. Waste products may be stored in leaves that fall off. Other waste materials that are exuded by some plants — resins, saps, latexes, etc. are forced from the interior of the plant by hydrostatic pressures inside the plant and by absorptive forces of plant cells. Plants also excrete some waste substances into the soil around them.

i know wikipedia isnt always the best source but i dont have any botany textbooks with me.

in terrestrial plants they do secrete some wastes through their roots, but this also server to attract fungus, nitrogen fixing bacteria and to ward off competitors. this is not really classified as excretion.

you can look it up for yourself :)
 
wearsbunnyslippers said:
@SuperColey1 - so why are we arguing, i agree 100% that adding co2 will be beneficial, but up to a point, adding more co2 after that is just wasting, we both saying the same thing :p

I'm not arguing...it is a waste BUT I wasted loads and pushed the upper boundaries. Makes perfect sense that if it is hard to reach a 'real' 30ppm then it will be much easier to reach the 'real' target if you inject more at the beginning. By real I mean the whole system and not just the area where the DC is. I could get 30ppm (grass green) at the furthest DC, 35ppm at the central one (lime green) and 40-45ppm at the nearest DC (very light green to yellow.)

If you are watching the fish carefully then the DC can be ignored to an extent. After all in tests Tom Barr found that the levels were around 8ppm at the substrate and 100+ppm right next to the DC. Were the fish staying away from the diffuser and staying near the substrate? Nope The whole school of Rasboras played around in the bubbles an inch or 2 from the diffuser. The 30ppm is basically a given range for the average. If you push in more yes you waste more but you are giving more chance to get to that magical number :) I don't waste any now though;)

name one plant in your tank thats leaves are literally years old? not stems or rhizomes, leaves...

maybe some extremely slow growing anubias or crypts, and if they are really that slow growing, there is no way the leaves have reached their saturation levels yet, when they do, they will yellow and die.

I'm not so sure that this can be taken as true, although I will have to take your word for it. I do have 18 month old leaves in my tank and yes there are some yellow ones. Normally though these are leaves that have become overgrown by newer leaves and then disintegrate. Remember this tank started it's first 6 months with 35-40ppm average CO2, 17x turnover and what proved to be pretty high light (LED) They were driven pretty fast for the first 6 months and then for the last year slowed down to a virtual standstill by light reduction and removal of CO2 injection.

As I said I wasn't trying to be finickity. It is just the first time I have heard about plants 'storing' waste and toxins. I have heard lots of times about plants producing waste though. Maybe they aren't as credible sources of info ;) Its nice to learn the reality.

AC
 
Hi all,
Doing a water change with tap water (which would contain much higher levels of dissolved CO2) would dramatically change the CO2 conc which the plants had gotten used to. The CO2 is unstable therefore you'll most likley get algae. So, the water changes are not advised. Well...maybe 3 a year.
All my tanks are low tech., have regular water changes and are nutrient limited, and I just don't believe the fluctuating CO2 hypothesis. For elevated CO2 levels you would need a supply under pressure (to keep more CO2 in solution), and a mechanism for creating CO2 in the potable water supply.

I use rain water for my water changes (about 10% a day, every day) and it will have equilibrated with atmospheric CO2 levels, but it would be easy to test the fluctuating CO2 hypothesis by measuring the pH of the tap water when drawn and then allowing the tap water to stand and out-gas for a couple of hours before use, if the pH has risen appreciably than the water initially contained some dissolved CO2 which has now out gassed. (Although this wouldn't work with a hard, very highly buffered supply because the carbonic acid - carbonate equilibrium equation would mean that huge amounts of CO2 would be required to measurably lower the pH).

From personal experience I would advice all low tech planted aquarium keepers to change a small volume of water every day.

cheers Darrel
 
if i dont learn at one new thing every day, i consider it a bad day...

plants use their vacuoles for transporting and storing lots of things, from metabolites and waste products to nutrients and even plain water.the space filling function of the vacuole is really important to plants, as they capture energy from light and dont move move to capture food in gernral. mechanical stability provided by the cell wall and turgor pressure allows plant cells to grow to a relatively large size, so they can occupy a much larger volume than animal cells. producing large cells by filling them with cytoplasm would be costly both on terms of maintenance and initial synthesis. so this is why they get filled with water and anything else that is available, including wastes and metabolites. plants are such super efficient little factories, it is absolutely amazing.
 
wearsbunnyslippers said:
in terrestrial plants they do secrete some wastes through their roots, but this also server to attract fungus, nitrogen fixing bacteria and to ward off competitors. this is not really classified as excretion.
Aquatic plants do not intentionally store waste products in this sense. That would be pointless. What they do is to re-assimilate certain products like ammonia which is definitely toxic, but which is definitely useful. The plant synthesizes certain proteins which use the NH3/NH4 molecules as part of the protein's molecular structure, effectively neutralizing the substance. Those metabolic products which are too energy expensive to convert or to re-assimilate are simply expelled out into the water column. These products are generally in the form or proteins or carbohydrates are fodder for micro-organisms external to the plant.

Proteins themselves, after serving their functions are broken down into constituent amino acids and are re-assimilated as other proteins, depending on the need at that moment.

The conversion and re-assimilation mechanisms often depends on carbon availability because those protein molecules are constructed around a carbon skeleton. Carbon deficiency therefore often leads to ammonia buildup, which leads to toxicity.

I think it was mentioned in one of the posts that when comparing the techniques of non-CO2 enriched versus enriched tanks, fundamentally one has to consider the speed and volume at which organic waste products are expelled into the tank, as well as the speed at which the organic waste products are broken down in the water column by decay and micro-organisms.

Proteins and enzymes are very complicated molecular structures. After being expelled some may take many days to be converted by the bacteria into nutrients that can be used by the plant. In a low light, non-CO2 tank this slow speed is matched by the slow uptake requirements of the plants. This is why growth is slow - low availability of carbon drives a low ability to use nutrients which means a low metabolism and a low expulsion rate of organic waste. On the contrary, high energy, fuel injected tanks pump massive amounts of carbon and nutrients into the tank. The high light powers the fast metabolic cycles which leads to the excretion of large amounts of carbohydrates and proteins into the water column. Since speed is the name of the game there is a problem with the proteins and carbohydrates in the water because they break down at the same slow rate poisoning the water due to their large quantities as they break down. The breakdown consumes large amounts of oxygen and results in ammonia fluctuations. These effects, under high lighting are trigger mechanisms for algae as well as leading to toxicity. That's why large and frequent water changes are important in a high tech tank. As per standard operating procedure (S.O.P) for The Matrix, everyone is hysterical about nutrient buildup instead of paying attention to the real culprit. The fact is that you can have as much nutrient buildup as you want, as long as the tank is kept free of the debilitating effects of organic waste buildup.
dw1305 said:
All my tanks are low tech., have regular water changes and are nutrient limited, and I just don't believe the fluctuating CO2 hypothesis. For elevated CO2 levels you would need a supply under pressure (to keep more CO2 in solution), and a mechanism for creating CO2 in the potable water supply.
Most peoples water are very high in CO2 and that's because the water is under high pressure, around 30 PSI, so the CO2 partial pressure is higher than that of atmospheric. Anyone can do the pH test you suggest and will find that the pH will drop significantly after an hour or two.

There are ways around the CO2 fluctuations such as your use of rain water or by allowing the water to stand, or even by changing the water after the photoperiod.

Cheers,
 
Hi all,
plants use their vacuoles for transporting and storing lots of things, from metabolites and waste products to nutrients and even plain water.
&
mechanical stability provided by the cell wall and turgor pressure allows plant cells to grow to a relatively large size, so they can occupy a much larger volume than animal cells.
Both are very true, plants are generally quite "leaky", but can be very efficient at partitioning toxic compounds, an example would be something like the Mendip lead mine spoil heap specialists Thlaspi caerulescens and Minuartia verna which hyper-accumulate lead (Pb), or the Bird's-foot Trefoil (Lotus corniculatus), which synthesise hydrogen cyanide, but which is only released when the plant is mechanically damaged during grazing.

The mechanical stability issue is also why Lemna spp. and algae such as Chlorella have such high potential growth rates, very little of their productivity is used producing structural carbohydrates (or chitin, bone etc), they can concentrate on cell division and the photosynthetic process to make the maximum use of possibly transient resources.

cheers Darrel
 
thats very interesting ceg4048.

it just goes to show that just because you might understand terrestrial plants doesnt mean that aquatic plants behave the same at all. i have always thought that the water change was pushing the reset button on the fert levels. but what you have explained, and i have confirmed this with a biochemist, opens a whole new door on water changes.

i have always understood the need for keeping your tank clean, removing dead and damaged leaves, make sure there is no detritus buildup etc. exactly for the reasons you mentioned, proteins, carbohydrates, amino acids, saccharides etc. being present in the water, attracting fungus and bacteria, and leading to algae. but aquatic plants doing this at an exponential rate in high tech tanks due to higher metabolism never occurred to me. i have always thought i could skip the odd water change especially if i have skipped a few doses, but now i am realising how important the water changes are regardless of the fert levels.

thanks a bunch, another reason i enjoy the discussions on ukaps so much!
 
I wonder would it be possible (in theory at least) to deal with the high levels of organic waste by having more filtration?

I know alot of high tech aquascapers aim for high turnover rates 10x or more but what about increasing the total amount of filter media or even doubling the number of filters etc. Could you get to a point where your filtration was breaking down the organic waste as fast as it was being produced and thus reduce the need for or eliminate water changes in a high tech tank?
 
Well, possibly, as long as you can pull the detritus away from the plant and substrate. The problem is that the stuff collects on the surface of the leaves in almost a glue-like manner, trapped in the epiphytic layer. You can see this when you do a water change by fluffing, shaking and preening the plants. You'll see a cloud of "dust" being shaken off. Digging up the substrate also shows just how much gunk escapes the filters. Given a choice I always choose more filtration to achieve the target flow rate versus powerheads. Of course you've got to clean the filters as well. Another problem is that no matter how much filtration you have, the nitrifying bacteria still need Oxygen to oxidize the ammonia right? So the stuff is still robbing the water column of Oxygen.

wearsbunnyslippers said:
...i have always thought that the water change was pushing the reset button on the fert levels...
I remember repeatedly reading Barr's "sermon on the EI mount" on different websites years ago. In those days, as I mentioned, everyone was uber-paranoid about NO3 toxicity. Discus lovers would demand that you perish the thought of actually adding NO3 to a tank. It was considered an unconscionable act which demonstrated blatant disregard for tank health by virtually every hobbyist on the planet. I suspect it still is to the vast majority. Tom had to convince them that you'd never have to worry about nutrient buildup because you'd do this massive water change every week to reset the tank. The phrase "reset the tank" was his way of reassuring the freaked-out masses that if you adhered to the dosing program and did your water changes, then you never needed to worry about toxic buildup. While this is a convenient fringe benefit, I reckon he knew that the water change scheme kills two birds with one stone; placates the nutrient haters and cleans the tank - bingo!

Because EI is interactive, it allows you to dose less than the baseline numbers without penalty under certain conditions i.e, less lighting, less CO2, high flow and so forth. Dosing less than baseline, and using less CO2 allows you to then do less stringent water changes since the organic waste production would then be lower than if you were dosing at the baseline level.

I'm one of only a few lunatics who decided to explore the boundaries of nutrient buildup (LondonDragon did it by miscalculation). I simulated it by adding theoretical buildup values immediately after a super massive water change. In that way I could separate the organic waste issue from the nutrient buildup issue. The result was zero algae and zero toxicity (short tern or long term). Only Captain Janeway, lost in the Delta Quadrant, can even come close to my dosing levels, which I dubbed "EI Voyager". Not recommended for the faint of heart.

Cheers,
 
Back
Top