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Nitrate problems

Thu Feb 11, 2021 10:14 am

Hi, I recently purchased a used cichlid tank set-up complete with fish. I am new to cichlid keeping but have had a koi pond for over a decade.

I transported about 25% of the original water and topped that up with warm treated tap water. I didn't originally clean the substrate which was pretty dirty but have since syphoned it twice. I have been doing daily water checks and whilst my levels are generally ok/good the nitrates are very high, at least 80ppm.
Nitrite has been 0ppm for days and has never been high. Ammonia did hit 1.0ppm but is now back down to 0ppm. I did a 25% water change a couple of days ago and then another 40% yesterday and added double the recommended dose of Seachem Prime each time but the nitrate doesn't seem to be going down.

The fish on the whole seem ok and feeding well although a couple are a bit nervous but i figured that have only just been moved about.
Other than continuing to do daily water changes is there anything else i should be doing? Any help would be greatly appreciated.

Re: Nitrate problems

Thu Feb 11, 2021 11:04 am

I would do daily water changes, increasing the amount each time until I was changing almost all of the water at once.
No reason to double the amount of Prime.

Re: Nitrate problems

Thu Feb 11, 2021 12:36 pm

I would also do a test on your tap water. High nitrate is a common problem in a lot of UK water. Beyond that, a lot of plants, even something like pothos in a big hob filter can eat up some nitratem

Re: Nitrate problems

Thu Feb 11, 2021 1:35 pm

Thanks noddy and Oscar6. Tested my tap water and that is 5ppm so higher than i would like but not terrible. I will keep up with the water changes and get some plants tomorrow. Currently i don't have any and was thinking of getting some anyway and had thought they might help with general water quality.

Re: Nitrate problems

Thu Feb 11, 2021 4:24 pm

I've read about some UK taps with 40ppm, so your 5 is really not bad. Plants are great if your fish will allow them. A lot of cichlids just rip them up. If plants fail, water changes are your nitrate control. You havent said what kind of cichlids, how many, size of tank? All relevant when considering nitrate levels.

Re: Nitrate problems

Fri Feb 12, 2021 2:43 am

Hmmmm..... Aquarium Water Changes.
Is Dilution - The Solution?
To - Water Pollution?
Well indeed, in this case it may be!
It's pretty simple, actually. In your case of the measured 80 ppm Nitrates in your aquarium? If you had immediately conducted a 50% water change after that measurement? You would have then measured a 40 ppm Nitrate level in the tank. (+5 for the Nitrates already in your Tap water).
It really is, THAT quick.
But get this.... the more fish you put in the aquarium? The faster the Nitrate level will build up in there! Oh yes....
It can get vicious, actually.
And is unfortunately the dreaded reality that just about all Cichlid keepers, (Esp. New World) face eventually. You HAVE to stay ahead of those Nitrates (They are Toxins). Striving constantly to keep them down to a relatively safe, 20-30 ppm in your aquarium. Or, your fish will almost inevitably become sick if the levels get too high. They may actually die. :oops:
And, for those of us that wind up with big fish - in too-small tanks? We may end up pushing some serious water in those too-small tanks to keep our Cichlids relatively happy and healthy. I'm talking 80 to 90 percent water changes in some cases - done twice per week!
And for most of us in this hobby, that's just more work than we can sustain to enjoy this thing. :?

Re: Nitrate problems

Tue Feb 16, 2021 3:33 pm

I tested my nitrates and I live in the south of UK. I could never get my nitrates under 40ppm even with 50-70% water changes. Turned out my nitrates are 40ppm out of the tap!!!! So I just go by that and know I need to do big weekly changes. Just how it is where I live.

Re: Nitrate problems

Tue Feb 16, 2021 11:13 pm

Hard to keep fish in those conditions. What do you drink?

Re: Nitrate problems

Wed Feb 17, 2021 9:25 am

A 40 PPM (40Mg/L) measured Nitrate level is going to put some serious stress on aquarium fish. New World Cichlids kept at those levels are at high risk of developing HiH/HLLE.
Beyond that, the problems with municipal supplied sources of tap water, definitely get more complicated....
The UK has set a limit of 50Mg/L on their municipal supplied tap water. That is considered a safe level to shower/bathe in or wash dishes. But, I'm not sure many people drink water right out of the tap in the UK.
The maximum allowable Nitrate level for U.S. supplied, municipal tap water is 10Mg/L. A study of Nitrate water contamination and it's causes and effects was done by Cornell University in 2020 and posted online in a report.

http://psep.cce.cornell.edu/facts-slide ... grw85.aspx

For our purposes as aquarium-keepers in areas with high Nitrate level tap water... these are the only reasonable solutions that can be done to remove or at least mitigate the Nitrates in the water,

- REMOVAL: Filter the tap water first through a Reverse Osmosis filtration system (A recent C-f member 'Monkeynuts' informed that he was doing just that for his aquarium. Nitrate elimination?). Water reservoir accumulation of the RO filtered water may be the only practical means to utilize this method for aquarium use.
- MITIGATION: Plant the tank heavily with aquatic plants. Stock very lightly with fish. Planted freshwater 'refugiums' are even being utilized more and more with some effectiveness as part of the overall, aquarium filtration system to capture Nitrates out of the aquarium water.
The environmental problem of ground water Nitrate contamination in the UK is addressed here,

https://consult.environment-agency.gov. ... p-2021.pdf

Kind of grim, actually... and this could be a look at contaminated ground water problems we may soon be facing in the U.S. :(

Re: Nitrate problems

Wed Feb 17, 2021 10:10 am

My mistake. I have just re checked my water and it is 20ppm out the tap! Great water in the south of the UK

Re: Nitrate problems

Wed Feb 17, 2021 10:29 pm

20ppm is the max I like the tank water to be just before a 50% water change to bring it down to 10ppm.

Re: Nitrate problems

Wed Feb 17, 2021 10:35 pm

There are natural ways to reduce nitrates. Some of them not applicable to a cichlid tank. You might want to look into this. It’s expensive and takes up to six months to take full effect but apparently it works. You need lots of it and it needs to be in a canister filter. There is a calculator somewhere.

Look it up, lots of videos about it on youtube. Some people also use similar porous material but the success rate doesn’t seem as good with those.

Last edited by Deeda on Thu Feb 18, 2021 12:56 pm, edited 1 time in total.
Reason: Link removed
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