Interested in Nitrate information

[1moretank]

I am not new to the hobby. I keep 10-12 tanks plus 2 quarantine tanks.  All but one have been running with few changes for over a year.  They are all average to heavily planted.  Some are heated, others are simply at room temperature.  1 or 2 could be considered over stocked a bit, but none are heavily stocked.  All tanks have 1 or more air stones.  None have any filtration except plants.  I have ran a HOB on 2 of the tanks when I felt the mulm was excessive  (about 2-3 weeks on each tank one time).  Most of my experience with planted tanks was in the soft water similar to what Cory has.  All of these tanks are using very hard water.  Until recently everything was doing so well that other than checking to see how my new water tested, I didn't bother testing.  Using Tetra easy strips, I tested my water by filing a 5 gallon bucket, adding Prime then waiting 2 days.  Results:  Nitrite 0, Nitrate 0, GH 150-300, Chlorine 0, KH 120-300, pH 7.2 - 7.8.  Tested 3 buckets on different dates, that's why there is a range.  I then used the last couple strips from that bottle and my tank results were about the same - except the Nitrates ranged from 40 ppm up to 200 ppm.  That scared me, so I ordered a new bottle of test strips.  Received them today.  Results are the same.  Some tanks are higher, some are lower, but they all test 80 ppm or higher for Nitrates.  My fish appear healthy, the guppies, platies, mollies, plecos and white clouds are all breeding, the fry are growing normally.  Only one tank has significant algae problem (hair algae).  I stopped the Easy Green once I saw the high nitrates, prior to that I was dosing weekly but not super consistently.

My questions:

Should I be worried since the only problem appears on the test strip and tanks don't seem to be struggling? 

Should I continue dosing Easy Green, I think plant growth has slowed a bit since I stopped dosing?

[Will Billy]

As a quick rundown, ammonia, nitrite, and nitrate are bad in pretty much that order. Low levels of ammonia and nitrite affect your fish more because they have a much more acute toxicity than nitrate. Which is why higher levels of nitrate i wont say is necessarily good, but are not as toxic as the first two. Coincidentally plants prefer nutrients in that order too, they metabolize ammonia much easier and faster than nitrate. 
 

Back to your question, fish can survive in much higher nitrate level than you have. Some reports as much as 800ppm. To reiterate they can survive, that does not mean its still healthy for them. So i dont think your nitrates are too out of control, however i would advise testing for nitrates before you add easy green, as it does spike your nitrate level. That way you get a good baseline of what your plants are absorbing, and you are testing for remaining nitrate, and not whats in the easy green. Testing before you dose in conjunction with visually inspecting plant growth should give you a better idea of what your plants are doing, while simultaneously keep an eye on fish parameters. If they are high before you dose, then you may consider a water change soon. 

[H.K.Luterman]

Will Billy's advice is good stuff. I just want to add, in case you haven't tried them, that you could use some pothos trimmings to help absorb the nitrates; stick them so that the stem is in the water and the leaves grow up out of the tank. Also, surface floating plants such as water lettuce and duck weed are great nitrate sponges, as well as hornwort. 

Edited March 6, 2021 by H.K.Luterman
typo!

[Will Billy]

2 hours ago, H.K.Luterman said:

you could use some pothos trimmings to help absorb the nitrates

I have recently added pothos to my tank too. My surface agitation is a bit to strong for floaters unless i made up some floating tube fence.   

[1moretank]

@will billy, i love the pothos holder, great idea.  I have super healthy hornwort in about half my tanks, jungle val is covering the top of most of the others.  I haven't used pothos in several years.  I don't change water normally, just op off, and there's quite a bit of evaporation even in tightly closed lids- I believe do to the hole necessary for auto feeders.   Those nitrate readings are capped at 200ppm by the test strip.  All the most recent test readings were after a month of no easy green.  Sounds like for now I will withhold easy green, let the hornwort get a bit thicker and just test and watch.  With everything still looking and acting healthy, I don't want to start a heavy water change  program.  If I can find some cheap pothos, I'll add those.   Thank you both for your help.

[Will Billy]

2 hours ago, 1moretank said:

, I don't want to start a heavy water change  program

No crucial need to start a heavy water change program. Small water changes can reduce nitrates, and add minerals back in. Overtime small water changes can add up. Just remember plants help with nitrates not remove the problem all together. Sorta like anaerobic bacteria, they help with nitrates but thats all they do is help. Anaerobic bacteria cant be expected to remove all nitrates just by themselves.