Removing Tap Water Nitrates with Nitra-Zorb (Experiment Results)

It could be worse. Before physicians could measure sugar in urine to make the diagnosis of diabetes mellitus, they would taste the urine sample for sweetness.
 
Hello. I've received a lot of help from @Colin_T and others with my unwell pleco (thread here), so I thought I'd offer up a small contribution to this forum.

As part of this ongoing nightmare, I was struggling to get nitrates down, and found that my tap water measures ~20 PPM by itself.

I dug around, and found a product by API called Nitra-Zorb. It's meant to go in the filter and soak up nitrates for a couple of weeks, then requires recharging in concentrated salty water. There are other nitrate-absorbing resin products too, but this was the one I went with.

I also found an old page from a defunct website (MJV Aquatics) detailing the writer's experience with using to "pre-treat" high nitrate water: https://web.archive.org/web/20210822140717/https://mjvaquatics.com/my-nitrate-fight/

I decided to give it a shot. The pouch came in a few days ago. It took a lot of rinsing to get the dust out first, and the pouch holding the material itself is pretty weak, so I eventually had to replace it.

I filled up a 5 gal bucket of tap water, put the pouch under the intake of a small pump, and let the water circulate:

View attachment 373508

Did it work? Here are the results. First, the fresh untreated tap water:

View attachment 373509

After 5 minutes:

View attachment 373510

After 10 minutes:

View attachment 373511

And just because I really wanted to get the nitrates down fast, here's what it looked like after 30 minutes:

View attachment 373512

Hopefully this will help some others in my situation. I'm sure results will vary with the pump used, body of water treated etc. The fella who wrote the article on the MJV website actually took some discontinued tap water filter device from API, and replaced the guts with Nitra-Zorb. Maybe something like that would work faster, but I'm not sure.

All the best

PS: If anyone has any advice, really struggling to help my poor pleco here: https://www.fishforums.net/threads/please-help-my-pleco-mouth-closed-not-breathing-normally.498300/ Thanks in advance.
My Nitra-Zorb came today but then I realised I didn't have a spare filter big enough to put the pouch/resin in, so thats coming tomorrow. I see that you didn't put the pouch inside a filter @blyatboy and it still reduced the Nitrate.

I intend to use it just for the tap water going into the tank because of its advertised ability to absorb ammonia, and me not opening wanting to interfere with my nitrogen cycle too much, with beneficial bacteria in mind. @TwoTankAmin do you think beneficial bacteria would still get there fill of ammonia from Fish if there was a resin that removes ammonia in the tank? The answer seems an obvious "no", but I was wondering if the beneficial bacteria might "grab" some ammonia BEFORE the resin consumes it?

Also, do you, or anyone else think that a resin that absorbs ammonia, Nitrite and Nitrate will remove minerals from the water and interfere with plant fertilizer and plant life? Thanks
 
Before I plumbed a nitrate resin binding filter into my sink, I was using NitroZorb bags in an Aqua clear 110 filter for nine months. My nitrogen cycle never crashed. I determined this by removing the resin every other month, and then measuring ammonia levels. Over the entire nine month trial, I had undetectable ammonia levels whether the resin was in the filter box or not.
 
Before I plumbed a nitrate resin binding filter into my sink, I was using NitroZorb bags in an Aqua clear 110 filter for nine months. My nitrogen cycle never crashed. I determined this by removing the resin every other month, and then measuring ammonia levels. Over the entire nine month trial, I had undetectable ammonia levels whether the resin was in the filter box or not.
That's really interesting, thanks. Did you switch to the plumbed Nitrate resin for long term convenience relative to having to keep recharging or renewing the Nitra-Zorb?
 
That's really interesting, thanks. Did you switch to the plumbed Nitrate resin for long term convenience relative to having to keep recharging or renewing the Nitra-Zorb?
Yes. Also once the resin bag was removed from the salt solution I would have to rinse it in over two gallons of distilled water before I was convinced it was salt free. I couldn’t use my tap water because it had nitrate.
 
Hey @AJ356, pause for a sec. @gwand might have been right after all, though in a different way.

I was puzzled by a drop of 1 GH in my tank after using Nitra-Zorb for a few big water changes. Lo and behold, I tested my tap water before and after Nitra-Zorb:

Before: 4.0 GH
After: 3.0 GH


As I'm caring for an unwell pleco, this was obviously not ideal.

I did a bit of digging and it turns out, the zeolite in the Nitra-Zorb could pull out cations like calcium and magnesium, especially in the absence of ammonia... And it replaces it with Na+ ions.

Meanwhile, nitrates are being replaced with Cl- ions. So indeed, given the right circumstances, Nitra-Zorb could indeed result in more sodium chloride ("salt") in the tank. Though not exactly in the way @gwand described.

Fortunately, the fix was quite simple:

I dumped the pouch into a sieve, then submerged and tossed it over a bucket of water repeatedly. Eventually, I separated most of the resin (tiny cream coloured spheres) from the zeolite (the rest of the darker, brown stuff). Then, I threw out the zeolite, then poured the resin-containing water through my mesh bag to collect the resin.

If you don't have a sieve the right size, you may be able to remove most of the zeolite by putting the whole mixture into a bowl, then dunking that bowl carefully into a bucket of water and "tossing" it a few times. The resin drifts with the water and is a lot more buoyant than the zeolite, so you may be able to separate most of it this way.

I then treated a new batch of tap water with resin-only pouch: Nitrates were still removed effectively, but GH remained unchanged.

I will edit the original post in case someone with sensitive fish comes across this thread. I think for this specific use case, a nitrate-specific resin product (without zeolite) would be much better. Hope all goes well with your Nitra-Zorb @AJ356.
 
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Hey @AJ356, pause for a sec. @gwand might have been right after all, though in a different way.

I was puzzled by a drop of 1 GH in my tank after using Nitra-Zorb for a few big water changes. Lo and behold, I tested my tap water before and after Nitra-Zorb:

Before: 4.0 GH
After: 3.0 GH


As I'm caring for an unwell pleco, this was obviously not ideal.

I did a bit of digging and it turns out, the zeolite in the Nitra-Zorb could pull out cations like calcium and magnesium, especially in the absence of ammonia... And it replaces it with Na+ ions.

Meanwhile, nitrates are being replaced with Cl- ions. So indeed, given the right circumstances, Nitra-Zorb could indeed result in more sodium chloride ("salt") in the tank. Though not exactly in the way @gwand described.

Fortunately, the fix was quite simple:

I dumped the pouch into a sieve, then submerged and tossed it over a bucket of water repeatedly. Eventually, I separated most of the resin (tiny cream coloured spheres) from the zeolite (the rest of the darker, brown stuff). Then, I threw out the zeolite, then poured the resin-containing water through my mesh bag to collect the resin.

If you don't have a sieve the right size, you may be able to remove most of the zeolite by putting the whole mixture into a bowl, then dunking that bowl carefully into a bucket of water and "tossing" it a few times. The resin drifts with the water and is a lot more buoyant than the zeolite, so you may be able to separate most of it this way.

I then treated a new batch of tap water with resin-only pouch: Nitrates were still removed effectively, but GH remained unchanged.

I will edit the original post in case someone with sensitive fish comes across this thread. I think for this specific use case, a nitrate-specific resin product (without zeolite) would be much better. Hope all goes well with your Nitra-Zorb @AJ356.
Brilliant update, thank you! Love your scientific approach. I have a GH test kit. Will let you know if My GH drops
 
It could be worse. Before physicians could measure sugar in urine to make the diagnosis of diabetes mellitus, they would taste the urine sample for sweetness.
Way to gross me out.
 
Brilliant update, thank you! Love your scientific approach. I have a GH test kit. Will let you know if My GH drops
There is a product called Cobalt Total Nitrate. It’s a resin that only binds nitrate. No Zeolite. It comes in a jar. You place the resin in a mesh bag, give it a rinse in nitrate free water and place in your filter box. It is rechargeable in salt water.
 
These are my results today @blyatboy for API Nitra-Zorb

Using the API nitrate testing kit. I used the Nitra-Zorb resin in about 25 litres of tap water. I didn't have an internal filter large enough to hold the resin, so I used a powerhead directed toward the resin in the 25 litre bucket

The nitrate started reducing from 30 minutes. Every hour after that, the nitrate would reduce until it became time for me to go to bed now, or soon.

In total, I had the powerhead and the resin in the bucket for about 7 hours

The picture shows you the start (right hand side) a few hours in (the middle) and about 7 hours in (the left)

I tested GH and was equal
KH was reduced by 1 drop (1 degree) in the resin treated water
pH was a fraction higher in the resin treated water, maybe it was 7.8 instead of 7.6

I'm not reading too much into the KH and pH differences, because they are quite subtle and we know our test kids are not laboratory standard
 

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What do you mean that “you tested GH and it was equal? “
 
What do you mean that “you tested GH and it was equal? “
I mean, I tested the GH and it was equal. The same GH in tap water before and after 7 hours in resin. I am only commenting on that as the original poster noticed a minor deviation in GH. Probably incidental I am figuring?
 
I wonder how much nitrate a bag of NitroZorb can bind to before it hits capacity and needs recharging.
 
I wonder how much nitrate a bag of NitroZorb can bind to before it hits capacity and needs recharging.
I'll post back on here and we will see. I'm interested to know two things, how often I need to recharge the resin, and then how often I need to replace the resin. I have 8 tanks right now. No big tanks, but I like doing 40-50% water change a week and am doing 50% every other day in fry grow out tanks
 

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