Nitrate Reactor

[elmo666]

Hello all, from Mr. confused. Having nitrate issues, so added purigen to my external eheim. Been doing some reading on de-nitrification, and very much like the idea of adding a nitrate reactor to help.
Problem is, so much conflicting advice. Approached my mate, a reputable aquatic retailer of 30 years, quite bluntly said no such thing, marine only, and if you did add one you will cause massively increased phosphates. Another retailer, bit of a techno geek, laughed at this saying an anaerobic chamber will work just as well in salt or freshwater as long as the right reagent is used.
Does anyone know enough to advise me please. Many thanks in advance.

 

[the_lock_man]

To be honest, I have never looked into them. Obviously, the way I control my nitrate is by regular water changes - but water changes are not just about removing nitrate, it also keeps other elements replenished. I can't see the point of a nitrate reactor, if you would still need to carry out water changes anyway.

 

[Lunar Jetman]

I agree with the_lock_man. Water changes are a better way to go. When you say you have "nitrate issues", can you elaborate? What levels are you seeing? What's the size of your tank and what have you got in it?

 

[elmo666]

Well, the problem I have, just recently discovered, is that I have greatly varying nitrate levels in my tap water. I'm not looking to reduce water changes at all, more so be able to increase the frequency of my feeding for my discus. Ideally it should be small amounts 5-6 times daily, but I've dropped this back to 3 because of the nitrates. As said, I'm not looking to reduce maintenance, more stabilization of water quality. I've read that these reactors can reduce levels to almost 0ppm when set up correctly. I've considered r/o, but as I've said in another thread (water maintenance) a ph crash is a distinct possibility, and something I wouldn't risk.
Levels are exceeding 80ppm, despite several weekly changes. Stocking in my 250ltr corner tank is 6 juvenile discus, 2 rams, 10 small black phantom tetra, 4 small clown loach and 8 dwarf coryadoras. Filtration is eheim pro 350 external. Lights and pressurized co2 on timers.
I'm fully aware of water changes and frequency, and really don't want to appear in any way rude, but I'm asking about nitrate reactors and their use in freshwater. No point in too many water changes if you're adding high nitrate water.

 

[Lunar Jetman]

I've just realised I've been commenting on your other thread! Happy to leave this as a discussion around nitrate reactors and have the other conversations on your other thread.

 

[elmo666]

Haha, ok, see you there

 

[the_lock_man]

Well, the problem I have, just recently discovered, is that I have greatly varying nitrate levels in my tap water. I'm not looking to reduce water changes at all, more so be able to increase the frequency of my feeding for my discus. Ideally it should be small amounts 5-6 times daily, but I've dropped this back to 3 because of the nitrates. As said, I'm not looking to reduce maintenance, more stabilization of water quality. I've read that these reactors can reduce levels to almost 0ppm when set up correctly. I've considered r/o, but as I've said in another thread (water maintenance) a ph crash is a distinct possibility, and something I wouldn't risk.
Levels are exceeding 80ppm, despite several weekly changes. Stocking in my 250ltr corner tank is 6 juvenile discus, 2 rams, 10 small black phantom tetra, 4 small clown loach and 8 dwarf coryadoras. Filtration is eheim pro 350 external. Lights and pressurized co2 on timers.
I'm fully aware of water changes and frequency, and really don't want to appear in any way rude, but I'm asking about nitrate reactors and their use in freshwater. No point in too many water changes if you're adding high nitrate water.

 
Not being a huge discus expert, I had a quick squizz at Devotedly Discus, who I believe to be quite reputable in the area of discus. They reckon 3 times per day feeding is perfectly adequate.

 

[elmo666]

Ok, did that say wether that was for juvenile or adults? I'm new to discus, but all the info I've read suggests more feeds, 5-6 per day, for young fish, 2 or even once for adults

 

[DrRob]

Can't comment much on discus, and I'm a great advocate of the solve the problem not the outcome approach.
 
However, I have done a fair amount of reading on nitrate reactors. They are indeed in existence, they're generally only commercially available for marine set ups but there's no reason why you can't have a set up for freshwater.
 
Essentially you want a reaction, either chemical or biological, that turns nitrate back into nitrogen. Biologically they're pretty much limited to the anaerobic reactors, not often used as they're a pain to set up, picky about flow rates, and tend to end up being bulky. The basic structure is a slow flowing, long, narrow, biological filter, which gives you an aerobic zone at the start that turns ammonia and nitrite to nitrate and uses the oxygen up, and then the anaerobic part that converts the nitrite.
 
Get it wrong though and you end up not using the oxygen in the start of the filter, killing off the anaerobic bacteria, and getting a nitrate surge.

 

[TwoTankAmin]

Why are you running co2? Why are you not worried this might crash your ph?
 
Water changes and live plants (even if its in a veggie filter) are two of the the better ways to remove nitrates in fw tanks, imo.
 
The nitrate test kits in the hobby are some of the least accurate as well.

 

[elmo666]

I'm running co2 as I have a fully planted set-up. I've used a denerlle drop tester to help determine the flow, and as I don't have soft tap water I maintain a stable ph of 6.5 over 24hrs. Why wouldn't I use co2? Alot less expensive than dosing with liquid carbon.If yo read the thread you'll realise that my tap water has HIGH nitrates, meaning any amount of water changes are not going to lower the nitrates in my tank, but will serve to replenish minerals and elements that become exhausted, as well as allowing substrate and filter maintenance. Again, two tanks, I'm looking for advice on nitrate reactors, not general maintenance.
Thanks for your input Dr Rob. I've been doing alot of reading, had surgery today so have the rare luxury of time on my hands, and it appears sulphate reactors are the norm for freshwater.

 

[malfunction]

From my comments on your previous post you'll know I share your frustration with seemingly high nitrates in my tap water. If you do opt for a nitrogen reactor, can you let us know how effective it is? I'd be interested in comparing it's efficacy with what I currently use (matrix, nitrazorb and nitratex).

In the meantime, if you're still examining other alternatives to combat your tap nitrates then some of the measures I used/researched were: nitrate sponges, tetra nitrate minus, denitrate and evolution aqua pure.

Good luck!

 

[elmo666]

Thanks, by all means I'll keep you posted malfunction and thanks for your comments

 

[TwoTankAmin]

I asked about the co2 as your answer was important. And I have read all of the thread before I posted. I asked since there are other reasons to run co2 than plants, one being to lower pH. If you are running a fully planted tank you should be seeing close to 0 nitrate. If you are dunning a high light fully planted tank you should definitely be seeing 0 nitrate. The one thing that could change that is if you are dosing nitrate as part of your fertilizing regimen.
 
And in a well planted tank there is way way less bacteria than in a similar tank w/o plants. The plants take up most of the ammonia produced in a tank which means none of it becomes nitrate. This is another major reason that well planted tanks are normally devoid of nitrate. Most of the ammonia doesn't become nitrate and what nitrate there is gets taken up by the plants fast.
 
Basically, there is no reason you should be having nitrate issues and thus no need for dealing with it. Which brings me to my next question, what are you dosing your tank with regularly (especially ferts but anything else as well)? My gut says you may also be adding nitrate via that route which on top of tap levels could keep NO3 levels up.
 
Unless you have your own well or a shared private well in an area with commercial sources of nitrate being put into the water table, then there should be a limit to how much NO3 is allowed in your tap from a water company. In the states this number has been 10 mg NO3-N/l for avery  long time (45 ppm on an API type kit). A well planted, co2 added tank should handle this level easily. If your tap levels are higher, then your tap is considered unsafe for infants to consume in the USA.
 
The last possibility here is that nitrates are not as high as you think. Of all the hobby test kits we use, the nitrate one is the least accurate and most prone to error. At best they should be used to indicate directional changes in levels.
 
Finally, if you do have a nitrate issue and are keeping discus, an ro/di unit would be a better and cheaper solution in the long term, imo.
 
If it is any comfort to you, I have both kept discus and run pressurized gas (and added nitrate to) a planted tank for a dozen years. I currently use ro/di, among other things, to maintain wild altum angels.
 
From http/yaphankcivic.org/uploads/Nitrate_Toxicity_to_Aquatic_Animals.pdf

 

[elmo666]

An interesting and in depth reply. I checked the regs for my local water authority, it states they must be kept below 50ppm. They're currently running at about 40ppm. One source of nitrate going is is from the frozen food I'm feeding. I did a small experiment after a friend who runs a lfs advised I should be rinsing it before use. I placed a small amount in a litre of water, tested after 30 mins. Very surprised to see extremely high nitrates. Although the test kits may not be particularly accurate, they're all we have to rely on.
my ferts don't appear to be to heavily loaded in nitrogen. I feed lush max trace minerals I bought online and aqua grow nutra feed.
since posting the thread I've purchased a three stage HMA filter and a 3 stage r/o unit. Instead of using 50/50 r/o tap water mix, I'm using 30% r/o and the rest is passed through the three stage carbon resin block. I then add Tropic Marin Pro Discus Mineral to correct the mix. So, I'm now adding nitrate free water with each water change. At present my readings are just where I want them. Ph 6.5, 0 ammonia and nitrite. Nitrate has come right down after several water changes, now at 20mg per litre. Kh is 5.