• 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

RO vs Nitrate removal filter

Notator

Member
Joined
15 Apr 2012
Messages
83
Location
Wisbech
In my area the water is heavy in nitrates - around 40/50ppm consistently, and higher at the weekends...
So my question is can anyone advise me on whether to go for an RO unit or just a Nitrate filter.
Any pro's and con's to either would be very much appreciated,
Jerry
 
Hello,
You're advised to ignore it and carry on. Why complicate your life? Plants need nitrate desperately, so why remove it?

Cheers,
 
CEG, are you stalking me? :)

Thanks, again, I'm not trying to be arguementative - just trying to understand... I'm sure I've read in more than one place that high nitrate levels are bad for the fish and should be under 20ppm...
 
Hi,
There are a lot of places that tell you that NO3 is bad for fish and that you should eliminate it. The problem is that nobody actually researches the "why" and "how" and so they don't really understand the context. People also mix and confuse information from different sources without paying attention to the details. NO3 is the end product of a toxic chain of events and it is actually natures way of detoxifying an aqueous environment. It is the chemical reactions that occur within that chain of events that actually does the damage, not the end product. When you understand this chain in greater detail, you will come to realize that feeding you fish is more dangerous to your tank inhabitants than the NO3 that is already in your tap. Read the following threads for some of the details:
viewtopic.php?f=21&t=12592
viewtopic.php?f=37&t=12656&start=30

Cheers,
 
Another way of looking at it is your lucky to already have Nitrate coming out of your tap! If the values you see are correct that is. The second link CEG posted there was one that I found was the most convincing in the Nitrate long term health affect and changed my thinking totally on the subject. In the big scheme of things that could affect long term health of your fish NO3 values are right down there below tapping on the glass.

More evidence if you need it is the vast majority of people in here will dose at quite high levels of Nitrate, some even higher than what is seen as the highest levels needed or EI as it's known. Thus far no one has reported any fish deaths or strange activity from the fish at these higher levels.

I have dosed EI levels in my tank for years and I have fish in there that have made it through 3 different tank set ups and by all reading on fish life span should have been dead about a year ago. One cory I have and a Siamese catfish that I used to start a new set up about three year ago have even moved house with me and are currently doing well in my latest set up :)

A lot of the scare mongering you here about regarding nitrate comes from fish only systems where the lack of plants sucking it out of the water can increase algae as algae will grow anywhere under any conditions. Even my rabbits (daughters) water bottle will grow algae and that gets washed out daily!In fish only systems it will accelerate algae growth so nitrate removers get used. Plus it gives the commercial fish suppliers something to sell :rolleyes: These rules don't apply in a planted tank and in fact the exact opposite is true that making sure there's enough nitrate in there is the problem. In your case you have a small buffer in your tap water.

Embrace your nitrates :)
 
Clive, I was just idly browsing at work and followed that first link of yours to the thread from 2010 - your dinosaur/plant analogy is definitely one of the best posts I've ever read on here. Rarely are hilarity and usefulness combined so effectively :lol:
 
In fish only tank's ,sans plant's, Nitrates are hard to accumulate to level's that may affect the fishes with weekly water changes.Cichlid's I have kept in particular,,do better at lower level's <40ppm.
With lot's of plant's,I have recorded nitrates as high as 80 ppm with popular hobbyist's test kit, which may or may not be accurate,but these level's are a result of inorganic mineral salt KNO3 that I add each week, as opposed to accumulation of fish waste,fish food,poor maint.My fishes, plant's, remain healthy. :thumbup:
With level's from the tap as recorded,, I too would choose more plant's over R/O or de-nitrate devices.
 
Unless you are keeping Crystal Shimp, levels arround 40ppm are probably fine. Carbon and plants will reduce it slightly.

The otto's might be a bit stressed with nitrates that high - they're pretty sensitive little things.

If you want to lower the nitrates, I recommend the Fluval lab series Nitrate exchange resin, it brought the nitrates of my tank water down from over 40ppm (tap water around here) to about 5ppm in a day or so in a 50L tank. You stick it in the last chamber in your filter canister. The best thing about it is that you can recharge it using aquarium/sea salt and its nitrate-nitrite selective.

Another thing to remember is that a lot of water conditioning products, like the tetra aquasafe, are designed to bind to the nitrates and render them harmless to the fish - but they will still show on the test.
 
Just dose everything but KNO3, and switch it with K2SO4. Do your water changes once a week, you should be fine.
 
Thanks to everyone - very helpful and very reassuring!
Wow there is a wealth of knowledge on this forum!

IT was the Otto's I was concerned for - although I hasten to point out they don't seem distressed at all - and also I had been considering investing in some crystal shrimp (Maybe I'll back burner that idea for the time being).

Thanks for all the great input and info folks,
Jerry
 
Neither Ottos nor shrimp care about nitrate. What they care about is clean water, and the same people who are paranoid about nitrate also refuse to regularly and frequently change their polluted water never realizing that fish are living in their own toilet. So the creatures contract diseases or are made more susceptible to stress by accumulation of toxins in the water that we ourselves add by dumping food in the water. Either the food goes uneaten and rots or if it is eaten it returns to the water as feces and urine. Ottos come from water systems which have millions of times more water so their toxic biological wastes have very low concentrations and they are not subject to ammonia and nitrite poisoning, or to the debilitating effects of hypoxia.

So this is what happens to so many tanks and why people have such difficulties. They poison their own water, refuse to replace that poison with clean water, claiming some gibberish about how parameters must be kept the same, and at the end of the day they blame nitrates for all their troubles. Get whatever fish or shrimp you want but CLEAN YOUR TANK frequently and in good measure.

Cheers,
 
I do frequent changes alright - but the level of nitrates never seems to drop much - UNLESS I fill my tank with really fast growing plants. The problem with that is that I then need to tend the tank every day pruning or it gets really unruly. I've swapped slowly but surely over to slower growing plants to reduce the daily maintenance but then of course I am no longer removing material from the tank at such a rate. Last couple of weeks the Nitrate in the tap water has been even higher than usual, God knows what they are playing at.

I've tried:
Changing food - using Hikari Micro Pellets to feed my 6 neons (twice a day...TINY amounts, almost all eaten immediately, doesn't even get to drop to the bottom)
Reducing Shrimp feeding to almost zero - quarter of a Hikari Algae Wafer every other day
Cleaning filter weekly - although I only flush the sponge/biostrate with the tank water coming out for changing...

Only thing I can think of is more thorough cleaning of the filter, but I'm afraid to do that in case I kill all the bacteria colonies....
 
If your really set on lowering your nitrates, use this stuff:

http://www.surreypetsupplies.co.uk/fluv ... -150g.html

Plants and the anaerobic bacteria in the filter probably wont remove it much faster than its being produced, and when you change your water its going to go back up anyway. So you could fill it up with RO water and then dose it with some trace minerals for healthy plant growth.

If you want to get really obsessive about your water quality, get a TDS tester (about £10 on ebay) :D
 
Hi all,
I do frequent changes alright - but the level of nitrates never seems to drop much - UNLESS I fill my tank with really fast growing plants.
Try some floaters, they have access to atmospheric CO2, so can utilise any available nutrients in the water fairly efficiently. The advantage is that you can hook them out really easily. Have a look a the "Duckweed Index" posts.
<http://www.ukaps.org/forum/viewtopic.php?f=27&t=21003> & <http://www.ukaps.org/forum/viewtopic.php?f=17&t=14400>.

Plants and the anaerobic bacteria in the filter probably wont remove it much faster than its being produced,
This honestly isn't true, plants are about an order of magnitude more efficient as water filters than bacterial only systems (even plant only systems will support a large amount of bacteria). If you have a system where oxygen isn't limited (like a planted wet and dry trickle filter) it can deal with huge bio-loads.

cheers Darrel
 
Do any particular plants use a lot of nitrate in their growth cycle compared to others or is it simply a matter of more growth = more nutrient requirement?

(I can't beleive I just said "simply"... I KNOW that's asking for trouble!)
 
Notator said:
Do any particular plants use a lot of nitrate in their growth cycle compared to others or is it simply a matter of more growth = more nutrient requirement?

(I can't beleive I just said "simply"... I KNOW that's asking for trouble!)

Reeds, but thats probably not practical :lol:
 
Notator said:
Do any particular plants use a lot of nitrate in their growth cycle compared to others...
Yes, of course. Plants that grow more quickly than others use more of everything than those plants that grow slowly. Fast growth equals more rapid nutrient and CO2 uptake. This is fairly simple and straight forward. Also, the more massive a plant is, the more nutrient and CO2 uptake is required to maintain that mass. So you can "get around" the trimming requirement by eliminating the fast growing plants and by having a very high density of slower growing plants.

What is less simple is the two way interaction between Nitrogen usage and Carbon usage. In order to construct enzymes and proteins, which are all built using Nitrogen/Carbon subunits called Amino acids, the plant requires high levels of carbohydrate. Therefore, adding more CO2 will increase the NO3 and NH4/NH3 uptake rates.

Cheers,
 
Hi all,
Fast growth equals more rapid nutrient and CO2 uptake. This is fairly simple and straight forward. Also, the more massive a plant is, the more nutrient and CO2 uptake is required to maintain that mass. So you can "get around" the trimming requirement by eliminating the fast growing plants and by having a very high density of slower growing plants. What is less simple is the two way interaction between Nitrogen usage and Carbon usage. In order to construct enzymes and proteins, which are all built using Nitrogen/Carbon subunits called Amino acids, the plant requires high levels of carbohydrate. Therefore, adding more CO2 will increase the NO3 and NH4/NH3 uptake rates.
It is just like Clive (and Mafoo with "Reeds") imply. If you have elevated CO2 levels in the water, or even better in the air (The 30ppm of dissolved CO2 aimed for with a drop checker is still only 1/10 of the 350 ppm CO2 in the atmosphere), carbon isn't a limiting resource and plants can utilise the available nutrients. I don't add CO2, so I use plants that have access to aerial CO2.

I've high-lighted Pistia, because although its growth rate and nitrogen removal potential is smaller than Water Hyacinth Eichornia crassipes it is a lot easier to grow in the tank. Pistia also also shows luxury phosphorus uptake.

I think every-one should have access to these papers:
Sharendu, S. et al (2012) "Luxury Uptake and Removal of Phosphorus from Water Column by Representative Aquatic Plants and Its Implication for Wetland Management". Soil Science 2012 <http://www.isrn.com/journals/ss/2012/516947/>.
The maximum capacity of luxury uptake of P under greenhouse conditions as exhibited by Pistia was further tested. Pistia individuals tolerated up to 50?mg/L phosphate medium and accumulated 6.12±0.95?mg/g?dw P after 35 days under greenhouse conditions. Up to 91% phosphate was removed from the surrounding medium within 60 days at 50?mg/L supply.
I think every-one should have access to this paper: Lu, Q. et al (2010) "Phytoremediation to remove nutrients and improve eutrophic stormwaters using water lettuce, Pistia stratiotes" Environ. Sci. Pollut. Res. 17 pp. 84–96 <http://irrec.ifas.ufl.edu/irsws/pdf/2/ESPR-QLu-Phytoremediation (2010).pdf>
Abs.
Water quality impairment by nutrient enrichment from agricultural activities has been a concern worldwide. Phytoremediation technology using aquatic plants in constructed wetlands and stormwater detention ponds is increasingly applied to remediate eutrophic waters. The objectives of this study were to evaluate the effectiveness and potential of water lettuce (Pistia stratiotes L.) in removing nutrients including nitrogen (N) and phosphorus (P) from stormwater in the constructed water detention systems before it is discharged into the St. Lucie Estuary, an important surface water system in Florida, using phytoremediation technologies......Water lettuce has a great potential for removing N and P, reducing water suspended solids and turbidity from stormwaters, and improving water quality.
cheers Darrel
 
See... I KNEW I shouldn't have used the word "simply". Knew it. :)

Now I know I'm going to regret this too...but...if:-

(The 30ppm of dissolved CO2 aimed for with a drop checker is still only 1/10 of the 350 ppm CO2 in the atmosphere)

Would I not be better pumping air into my reactor and not worrying about my fire extinguisher collection?

Also, could anyone give me some names of small, dense plants... Keyword there being small... ?
 
Notator said:
Now I know I'm going to regret this too...but...if:-

(The 30ppm of dissolved CO2 aimed for with a drop checker is still only 1/10 of the 350 ppm CO2 in the atmosphere)

Would I not be better pumping air into my reactor and not worrying about my fire extinguisher collection?
Err.. I think you might be missing the point. Darrel is alluding to the fact that when CO2 is dissolved in water it is much less available to plants than it is when it is dissolved in air. Air pumped through a reactor has a CO2 concentration of 350 ppm, but FE CO2 pumped into your reactor has a concentration of approximately 1,000,000 (1 million) ppm. Please review the mathematics and rethink this strategy.

Cheers,
 
Back
Top