Discussion in 'Algae' started by George Farmer, 11 Feb 2008.
Some of you may have seen this.
For those that haven't -
Many thanks George, that does explain alot of things.
EDIT: A note for historical purposes. This is to reflect the fact that Dusko has made the appropriate changes to his article following the discussion on this thread. The data on the Dusko link shown by George above is now consistent with the Barr principles. The text below in this post addresses the data that was on Dusko's website prior to his modifications on his webpage.
Err... Yes except there are some fundamental flaws which should be noted, primarily because the author bases his/her explanations on the premise that somehow nutrients are a root cause of algae, which I believe is preposterous. I'm not sure how the author could have studied Tom Barr's EI principles and yet still have conjured up this premise. That nutrients don't cause algae is a Barr principle Numero Uno.
Here are some examples of what I find objectionable. These are taken out of the context of the paragraph but are cited as an example of the premise:
"...Fast growing stem plants are very famous for keeping algae at bay for their ability to uptake nutrient in no-time. .."
This is not how fast growing stem plants combat algae. They do it by removing ammonia from the scene.
"...Since algae are nutrient scavengers and much simpler life form than plants, they will take an advantage in unbalanced systems..."
Algae don't "scavenge" for nutrients. That is not what triggers a bloom. They can survive with zero nutrients or with high nutrients. I agree that they do take advantage of unbalanced systems but it's not necessarily due to seeking nutrients.
"...Liquid iron will, if over dosed, favour Hair algae..."
Sorry, don't agree with this. While Fe may be used by hair algae when present there is no correlation between the presence of high levels of Fe and the appearance of hair algae. The hair algae will have been triggered by the presence of ammonia and will then feed on Fe. Hair algae can be induced with ZERO Fe in the water column.
"...It is very important performing 50% water change per week. This way we limit nutrient build-up..."
Nope, the real reason we do water changes is to limit ammonia build up.
"...The best fertilizing method so far is the Estimative Index method (by Tom Barr), where nutrients are dosed every 2-3 days instead of adding all nutrients at once giving algae chance to scavenge..."
Umm, OK I'll agree to the first half of the sentence but the second half is misguided. The whole "algae scavenging for nutrient" theme is off the mark and can subsequently lead to invalid analysis/conclusions.
"...When buying new plants, before planting, it's good to soak them into a weak household bleach solution for two minutes. 1 part of bleach (don't use bleach that has lemon, orange or any kind of scent) to 20 parts of water..."
No, this is definitely not good. Bleach will damage the plant as well as the algae, slowing it's transition to submersed state and giving algae a head start. Throw the plants directly in the tank and forget about this recommendation, or just wash with water.
Other than these key points the article is very complete and is a good reference. He/She stress the importance of dosing nutrients and clearly explains the differences in application of low tech versus high tech. There are also some nice pictures of algae to help identify.
Sorry to be splitting hairs a bit Clive but I think the reason for the water change is twofold - it puts a cap on nutrient levels before they get too high, resetting levels and removing the need for test kits as well as reducing levels of ammonia and algae spores. If it was just ammonia then water changes would be obviated by putting purigen in your filter and perhaps dosing with one of those liquid zeolite products once per week.
Dusko, the author, runs a lovely blog - well worth checking out, I particularly enjoyed his reef blog since I know nothing at all about that side of things but there is also some nice stuff on his other experiences.
Yes I hear you mate, but if you wanted to put a cap on nutrient levels all you'd really have to do is to stop dosing for a few days. The problem in high tech tanks is that of organic waste which, when built up to sufficient levels starts to produce ammonia at a higher rate than can be pulled out of the water column by Purigen/Zeolite/Carbon - each of which Barr recommends by the way. Although...thinking about it I suppose you could add a super massive filter completely filled with zeolite/purigen. I'm going to have to check that out Ray. Good point! Barr suggests that substrate vendors start using zeolite in their substrate formulas.
In his initial studies it was unclear what level of nutrients could be considered "too high" (toxic to fauna/flora.) He has since determined that very high levels can be in the tank without fear of toxicity or algae.
You'll also note that he recommends multiple water changes per week for the initial few months of a tank startup. This has nothing at all to do with nutrient buildup and everything to do with ammonia removal.
Some time ago I tested this myself. I simulated nutrient buildup by adding 50-60ppm NO3 plus 6-9ppm KH2PO4 4x per week. The trace dosages were also multiplied accordingly. This test was performed over a period of 6 months to determine the short term toxic and algal effects of nutrient buildup. RO water change interval was 50% 1X per week, however immediately following the water change the high dosage was applied. Tank size 6ft x 2ft x 2ft (150 USG). Lighting was 1/2 kilowatt PC T5. Here are the results after 6 months. I apologize in advance for the poor photography.
If you can forgive the flare from the flash I include this photo to show they type of fish in the tank and their health indicated by their coloration. Note that there is some inevitable algae in the front gravel. It's hard to appreciate the scale here. From substrate to water surface is perhaps 20 inches.
Close up of various swords. Not a spec of algae. Some algae on the hardscape.
Aponogetons gone wild.
Here is an overall shot after a major trim and thinning, again not very artistic but illustrative. The right side gravel is infected but is easily turned over at water change time. On the left, even the Anubias, notorious for getting GSA is completely clean.
If you accept the premise that the extra dosing adequately simulates nutrient buildup, then these results show that nutrient buildup is not really a concern. In this tank Apistogramma Cacatuoides bred several times over that period and the pair lived for almost 3 years. Other than the right side foreground gravel ( a riddle I never solved) no algae was present and plant growth was unbelievable requiring an unacceptable level of maintenance i.e trimming etc.
The point I always try to make is that we need never really worry about nutrient build up at all. If we worry about high nutrient levels we'll miss the boat completely. We instead should always focus on organic waste and spore removal. If we eliminate ammonia from the tank a nutrient buildup merely results in higher plant growth rate, which is a good problem.
The strange thing about this site is that it comes with Tom`s endorsement. I agree with everything you say on this thread, Clive, but never questioned the linked site when Tom first mentioned it.
I think I`ll stick to our own James` guide.
How many 6' tanks do you have Clive?! For months I've been thinking "this guy really knows his stuff, his plants must grow like crazy" so its nice to finally see that your tanks are super lush!
This is a very interesting question. I would think a filter chock full of purigen and zeolite would pull a lot more ammonia out of circulation than a water change. For example, we have a tank with fish and even shrimp living in it meaning ammonia must barely be measureable. Yet somehow a tiny unnoticeable (to our test kits) ammonia spike is enough to trigger an aglae outbreak. How on earth can a 50% water change once per week help reduce the resident ammonia more than our biological filters, substrates and thriving plants are already doing?
It could be if you gravel vacuum and remove dead/dying leaves at the same time that this is the key factor - removing the sources of ammonia - not the water change itself (although that would help clear up after the disturbance)?
Could be that the key here is not the ammonia part but the organic part - that oraganic elements trigger the algae?
This maybe explains something that has been baffling me. When I started out I cycled my fully planted tank with ammonia - I dosed 1ppm/day for 3 weeks until ammonia tested at 0, but I never had an algae outbreak, NB, this was not a high tech tank so that could be why I got away with it, also, it was brand new so only algae spores came in with the plants. But note, my biological filtration was stripping 1ppm + backlog of ammonia from the system per day. I'd hazzard a guess I could have upped the dose to 2 or 3ppm/day and the filter bacteria would still have handled it. Does a high tech tank really produce more ammonia than 2 or 3ppm/day?
I've had three at one time but the water changes got the better of me and now one is enough. The photos of the EI experiment above was done between 2003 and 2004, and that's the same and only tank I have now. The photos were taken with a borrowed primeval digital point-and-shoot. I don't think they had even invented the term megapixel when that camera was new (probably kilopixel).
Wouldn't it be great if it turned out that I didn't even have a tank and that I was just repeating stuff I had seen on the Discovery Channel? Or what about if I wasn't even a real person, just a program written by Matt running on his newly built computer to periodically submit obnoxious posts? What a great story line!
Well my aquascapes are really nothing special and the tank is more of a laboratory than a garden so I don't bother to post them. One things for sure though, I've run that tank at baseline EI, 2X EI and 3X EI. In my particular case I've found that 2X EI works better for me. Here is the same tank run at 2X EI started up last Aug:
Yes, I know, it won't win any contests , especially with those god-awful spray bars:
Again, algae on the hardscape is a riddle.
This is P. Stelleta from Tropica, only three weeks in the tank. No bleach, just plenty of CO2 and nutrients.
This is the same area a few months prior to adding the P. Stelleta. No scrounging algae can be found here.
This is the middle area of the tank. OK, so there is a bit of algae on the wood.
Here is the right hand side:
Alternanthera is plenty red for me. I don't need to limit nitrates.
This is Ludwigia ovalis. It's kind of reddish, but only as it approached the top.
Finally, the underside of a Java fern.
Never can anyone convince me that either nutrient limiting is a required policy or that "excess nutrients" is a problem. Now, strands of hair algae do appear. This is a signal that I should change some water, but I know why I should change it. Not because of excessive nutrients but because of excessive ammonia.
I think Ray that due to the amount of light, bacteria colonies cannot respond quickly enough if there are ammonia spikes. The higher the light, the more quickly the algae spores respond to the spike. Ammonia is constantly being produced at some baseline rate. The bacteria colony population is at a level to consume that nominal rate. To consume the spike the colony must increase it's population but it's response to generate a population increase is slower than the algae can sense and respond to the increased ammonia production rate.
I can only speculate that 3 billion years ago when algae were developing, perhaps the nitrogen content of the water was found in ammonia so that became the trigger for their reproduction. In a low tech tank there can be a higher ammonia spike without a bloom because the light is much lower, so I guess this one of the keys. Algae are faster and more adept at responding to environmental changes.
Wow clive I'm speechless. That is truely impressive and for anyone that says Estimative doesn't work, this is the proof it does.
Thanks for sharing
That's OK we did wonder and to be honest I'm just a PEARL script re-posting the silliest questions I can find screen scraped from other aquatic forums!
Actually a nice "Dutch" look (I'm not qualified to say if you follow all the Dutch rules, mind). Incredibly lush - very nice indeed.
Fair enough, sounds plausible.
You don't need to speculate - see this quote from the Wikipedia entry on the earth's atmosphere which gives an idea of the kind of atmosphere the original algae evolved in: http://en.wikipedia.org/wiki/Earth's_atmosphere#Evolution_on_Earth
About 4.4 billion years ago, the surface had cooled enough to form a crust, still heavily populated with volcanoes which released steam, carbon dioxide, and ammonia... As oxygen was released, it reacted with ammonia to release nitrogen; in addition, bacteria would also convert ammonia into nitrogen. But most of the nitrogen currently present in the atmosphere results from sunlight-powered photolysis of ammonia released steadily over the aeons from volcanoes...
This still puzzles me - by the time you change the water the ammonia spike will be long gone. The background ammonia level is handled by the biological filtration and plants (I expect there is a small spike every night as the plants stop uptake and the bacteria need to adjust). So why do the water change? I remain unconvinced that its necessary to get rid of the ammonia except in order to remove mulm and other debris.
Water changes to remove ammonia? If you get any build of ammonia in your tank then something is wrong that water changes alone will not combat. Add more filtration, more plants, whatever, but any ammonia level is surely indicating something other than the need for changing water.
Oh, and if you class ammonia as a nutrient, which it is, then fast growing stem plants combat algae by taking up all ammonia - if they'd said that instead of 'all nutrients' then the paragraph is, imho, more accurate.
Cheers James. Thanks for the compliment. I firmly believe that the presence and availability of unlimited nutrients/CO2 allows plants to develop their ultimate expression of form and function. Don't look now but I actually stole the general scape ideas from that 120cm on your web page
Hi Ray, Well, remember that the spike is a double edged sword. If you could take a reading, a snapshot in time you would see a spike in the ammonia concentration, but this also indicates a spike in ammonia production, which, given time would be attenuated by bacteria and plants certainly. As we discussed earlier though, this is a race - how quickly can the plants/bacteria respond to the change in ammonia production versus the trigger mechanism of algal spores. By the way, the debris you would be removing with the water change is a contributor to the increased ammonia production as it decays if left in the tank. Therefore removing water immediately reduces the ammonia content, removes the source of ammonia production and removes algal spores which attenuates their response.
Ostensibly, your analysis is correct, except respectfully, there is a critical misconception. Hobby grade ammonia test kits are designed to indicate levels of ammonia toxic to fauna. Algae blooms are triggered by ammonia concentrations that are two to three orders of magnitude lower than what can be registered on the test kit. When the test kit reads zero that means it's safe for your fish - that's all. Ammonia is constantly being produced in the tank. It is never zero. If it were zero and if it stayed zero the bacteria in your filter would starve to death. Anything that dies or decays produces ammonia. Fish waste and food decay and cause ammonia. The buildup and ammonia spike we are talking about can never be registered on any hobby grade ammonia test kit.
In a high tech tank I would never class ammonia as a nutrient. It's a scourge and the bane of my existence. That's what it is. The wise gardener attempts to eradicate it and it's source completely from his tank at all costs. Really that's just semantics though. Plants convert NO3 to ammonia internally before stripping the nitrogen. It is therefore the nitrogen that is the nutrient. Umm...yeah, that's another failure of the author in that article to miss that point. The nutrients are really N, P and K.
Did you know that the N source in Tropica+ liquid is NH4NO3?
Is that classed as dosing NH4?
Or you could class it as dosing explosive! Ammonium Nitrate is very handy in that area too!
Yeah, I know. That's how it reads in my book. I'm such a fanatic that I've decided to purge my stock :!: TPN+ and Brighty are now on my UN Sanctions List...I've got 2 gallons of this stuff left. I'll trade for equal volume of TPN classic.
So let me try to summarise:
- We have heard that very small, hard to measure ammonia spikes trigger algae spores in a high tech tank (is there a Barr report or somewhere where this is proven?).
- We have seen that water changes are helpful to reset nutrient levels but not necessary because, as Clive's experiments show, excess doses of nutrients are not a problem to plants or fish, nor do they cause algae.
- We have seen that water changes remove algae spores and combined with removal of mulm and decaying matter reduce ammonia production in the tank. Since ammonia triggers algae spores this will reduce algae.
- We have not seen that water changes actually diminish ammonia directly since the tiny spikes that trigger algae can occur any time and a water change is only at one moment.
So far so good - are you in agreement? I'd like to play devil's advocate and propose the following hypothesis:
If this is true then the big filter choc full of zeolite and purigen is the way to go. I also suggest blowing your ammonia right down the tank to the filter inlet, triggering algae spores as it goes, is an error. :idea: This is perhaps heresy, but I suspect the best way to feed your big filter (or perhaps a big sump) is through an undergravel filter that sucks the ammonia straight down into the substrate before it has any chance to trigger algae spores at all !
Hi Ray, yes lets see where we are:
Yes, the analysis and conclusions of his research are addressed in the fabulous Nitrogen Newsletter Dated June 2005.
Well, no, I guess I'll have to disagree. The ammonia production rate increase results in the spike. Your assumption is that the spike occurs and then is immediately abated by the consumers of ammonia in the tank (plants, bacteria, algae). At these low levels of ammonia and with the presence of NO3 in the tank the plant uptake of ammonia is not as efficient as that of algae. The bacteria colony also requires time to increase their population in response to the spike. Algae respond to the spike but it does not mean that they consume enough to completely attenuate the spike. Because there is a spike in the production, ammonia continues to enter the system at a higher rate than consumption.
Neither production nor consumption is static and each has their own rules. So let's say the baseline ammonia content was 0.005ppm. This means that the ammonia production rate (milligrams per hour) minus the consumption rate (milligrams per hour) is almost zero. A fish dies and decays unnoticed in the corner. The production rate accelerates and the difference is higher. More milligrams of ammonia is dumped into the water column. If you could measure, let's say the reading is now 0.008ppm. The three contestants now respond to the increased concentration but the bacteria colony may take a week to increase their population and to consume the higher content. How long does it take to cycle a tank? 2-3 weeks and that's with a very high ammonia concentration. Meanwhile the dead fish is still pumping ammonia into the tank at a higher rate, while consumption only increases slowly. If we do a 50% water change right now the ammonia content drops from 0.008ppm to 0.004ppm which was less than the baseline. If we wait, the difference between the production and consumption might not equalize for days. It's during this period of imbalance plus high light that algae strike.
The example I use was a dead fish, which is easy to visualize, but this is an exception, not a rule. Here I have to give credit to the author of the article in that he/she states that poor dosing and subsequent nutrient deficient damages plant health. Cell structure breaks down and decays. Nutrients and ammonia held in the various chambers can then escape into the water column. Although the tanks overall ammonia concentration might not increase that much, locally, in the neighborhood of the leaf that is "bleeding" the concentration is high and algal spores already on the leaf and bloom and the strands will stay attached to the leaf feeding on the leaf contents like a vampire.
When you see algae on a leaf, it means that leaf is unfit and is bleeding. It is unfit due most likely to inadequate nutrients or inadequate CO2. That's why NO3, PO4 and even NH4 test kits are redundant. The algae is your test kit. When it appears it means your nutrients/CO2 are too low, regardless of the kit readings.
Ammonia is also in the substrate in quite high concentrations. When you dig up plants or otherwise disturb the substrate you immediately dump the ammonia into the water column.
As George alluded to, some vendors use ammonia salts as their source of N, which I find completely astonishing. Probably the levels are low enough if dosed properly, but I don't see the point. I might be missing something so I want to study this some more.
Well, see the item above. The more water you remove the more ammonia, spores and detritus you remove.
Let us know how you get on mate. I read somewhere that plants have an 'easier' time using it for their N source than KNO3. I'm no biochemistbotanist though...
But I know I don't get algae.
I looked at ammonia additions to tanks a while ago. A few notes for you.
Seachem Nitrogen uses guanidine and potassium nitrate as their source for N. Guanidine is similar to urea. I think I'm correct in believing that plants can utilise the Urea but algae can't - may need to check on this.
Tropica use ammonium nitrate but I think it is bound up somehow so it's not like adding ammonium salt - need to confirm this.
Some people have been exprerimenting using urea with good results, but others haven't.
A thread just started on APC might be of interest - http://www.aquaticplantcentral.com/...aquarium-plants-preference-ammonium-over.html. Follow Freemann's link to the Barr Report as well.
Nice one, James. Always one step ahead, as usual, my friend.
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