High Nitrates

duanes

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Filtration?
As mentioned, average filtration does not remove nitrate, because nitrate is waste product of filtration.
Frequent Water changes are the best way to reduce nitrate.
An occasional large water change will not make much of a dent.
I do 30 to 40% every other day water changes on my 300+ gallon system, and nitrate remains undetectable.
D8CA7278-2FD9-40F1-B922-8F93002F34A7_1_201_a.jpeg
My latest nitrate test above.
But I also use lots plants (aquatic and terrestrial) , because they directly use nitrate.
But to make a dent, the plant weight must outweigh the fish many times over.
DCDBF189-D440-4AB9-946E-141C126231C5_1_201_a.jpeg
In the U.S. the MCL (maximum contaminant level) for for nitrate in drinking water is 10ppm, most systems don't come close to that.
Where I worked as a chemist at the water purification plant, average nitrate in tap water was 0.20 ppm.
High nitrate is usually only problematic in drinking water, in agricultural areas where high amounts of fertilizer are used
 
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tlindsey

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I have a 280gallon 72x30x30in tank stocked with 2 silver arowanas, 3 cichla monoclus, sturgeon, 7 silver dollars, indonesian Tiger and an oscar. Nitrates are at 80ppm and it would never come down despite a huge water change. I use direct tap water + water conditioner as my water source. Can you recommend some ways to lower my nitrates? Thanks!
Welcome aboard
As others stated water changes and filter maintenance will help reduce nitrates. You may need to do water changes bi-weekly or every other day. Also water changes should be done regularly.
 

dogofwar

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Yes - with a bio load like that, nothing is going to get nitrates down like large, frequent water changes and regular filter cleaning.

My fishroom is on a (semi-) auto water change system that drips water into all of my tanks whenever I turn the water on. I usually run it for 10-15 minutes (which changes 2-3 gallons in small tanks and 2-3 times that in larger ones) twice per day. At least a couple of times per week, I run it longer and change closer to 50-60% of tanks (maybe more, who knows). And I still don't have zero nitrates...

Welcome aboard
As others stated water changes and filter maintenance will help reduce nitrates. You may need to do water changes bi-weekly or every other day. Also water changes should be done regularly.
 

Toiletcar

Goliath Tigerfish
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It’s healthy to have some nitrates. I like to keep my tanks around 5-10ppm nitrates. Other than doing water changes, I clean out my canisters w/ tank water every 2 weeks. I also recommend pothos as a terrestrial plant to reduce nitrates.
 

MacaHobby

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It’s healthy to have some nitrates. I like to keep my tanks around 5-10ppm nitrates. Other than doing water changes, I clean out my canisters w/ tank water every 2 weeks. I also recommend pothos as a terrestrial plant to reduce nitrates.
Do pothos contribute a bulk in decreasing nitrates? Or I should keep a ton in able to see some results?
 
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MacaHobby

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Yes - with a bio load like that, nothing is going to get nitrates down like large, frequent water changes and regular filter cleaning.

My fishroom is on a (semi-) auto water change system that drips water into all of my tanks whenever I turn the water on. I usually run it for 10-15 minutes (which changes 2-3 gallons in small tanks and 2-3 times that in larger ones) twice per day. At least a couple of times per week, I run it longer and change closer to 50-60% of tanks (maybe more, who knows). And I still don't have zero nitrates...
Yes - with a bio load like that, nothing is going to get nitrates down like large, frequent water changes and regular filter cleaning.

My fishroom is on a (semi-) auto water change system that drips water into all of my tanks whenever I turn the water on. I usually run it for 10-15 minutes (which changes 2-3 gallons in small tanks and 2-3 times that in larger ones) twice per day. At least a couple of times per week, I run it longer and change closer to 50-60% of tanks (maybe more, who knows). And I still don't have zero nitrates...
What's your water source? As for my case I am using tap water and I hate seeing my tank going through a temporary bacterial bloom which makes it very cloudy but would clear up after 10hrs

IMG_20210522_232318.jpg
 

Rocksor

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Do pothos contribute a bulk in decreasing nitrates? Or I should keep a ton in able to see some results?
Unless you have a ton of pothos, you won't see a decrease in nitrates, just a slower increase in nitrates. For example, if your tank takes 3 days to hit 30ppm in nitrates before pothos added, then with enough pothos, you will see that it hit 30ppm in 7 days.
 

MacaHobby

Feeder Fish
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Unless you have a ton of pothos, you won't see a decrease in nitrates, just a slower increase in nitrates. For example, if your tank takes 3 days to hit 30ppm in nitrates before pothos added, then with enough pothos, you will see that it hit 30ppm in 7 days.
I see, then adding Pothos would be very beneficial on the intervals and frequency of my water changes this is good to lower my workload. Thanks! ??
 
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Matteus

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I see, then adding Pothos would be very beneficial on the intervals and frequency of my water changes this is good to lower my workload. Thanks! ??
Welcome to mfk. First off, I would like to applaud you for actually testing your water. Lots of people ask for help and don’t give test results. They just say “it’s fine” lol

I would say to get caught up a bit on the nitrates, like most have already mentioned. Do a number of smaller water changes 20-30% daily to pick away at the nitrates. In that time clean out as much of the gunk in the sump that usually collects, but don’t mess around with any of your bio media, since you are already in a bloom. I typically always use tank water to rinse my bio media so it affects it less and I have never had a bloom happen.

the reason for a number of smaller water changes, is to keep the system somewhat stable. If you do a big wc after it being so high it can shock the system which is likely a contributor to the bloom.

I would recommend getting a bunch of pothos as well. Every little bit counts at this point.

once you get the nitrates down a fair bit it will be easier to keep it lower with more regular water changes. The sad reality of having a heavily stocked tank is more maintenance. To the eye it may not look like a heavy stock list, but almost all of the fish you have in there create a big bio load for their sizes. When they create a mess and leave gunk hanging out in the tank or sump, the system may be able to break it down, but it is still creating more nitrates than necessary.

Whenever I notice that my nitrates are high even after wc schedule, I look to my filtration, clean out my canister, or sump etc. But I usually only do one at a time, I don’t clean both because if you wipe out too much of the good bacteria with a service it can cause the bloom.

good luck and keep us posted.
 
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