# Nitrate spike



## dinop (Jan 31, 2010)

Hey guys, so my nitrate has gone from being normal to through the roof.

Its very strange, everything seemed very stable and out of nowhere it goes up.

I do weekly water changes (+/- 25%)
Here are my current readings:

Ammonia - 0 ppm
KH 4 dkh / 71.6 ppm
PH 7 - 7.2
NO2 - 0 ppm
*NO3 - 40 ppm*

Ive got about 6 different assortment of plants lots of driftwood and various rocks purchased from LFS (Not sure what type of rocks they are)

Anyone have any ideas as to where I should start? I did a 30% water change when I saw the high nitrate last night, and did my second tests to find the nitrate has not changed.

I dont believe I over-feed, regularly maintain my eheim filter.

I was considering some type of chemical to lower the nitrate, but any suggestions would be apreciated.

Dino


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## carmenh (Dec 20, 2009)

No point using chemicals without figuring out why...
Could something have died and gotten wedged in where you are missing it?
Are you siphoning a portion of the gravel with each water change?
What kind of bioload do you have?
Are you using fertilizers?
Lastly, are your test kits fresh? Expired kits can show false readings...


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## dinop (Jan 31, 2010)

I cant seem to locate anything dead. I will check the inside of my filter again..

I dont have much room between plants. Would you recommend siphoning as close to the plants as possible?

I have a 90 gallon tank with lots of tiny fish. neons, guppies, 4-5 german rams.
all in all I would say I have 35-40 fish.
I have substrate as gravel, CO2 setup too..
I tested my tap water (No3) just to see if there was a difference and it came up at 0ppm if I recall.

technically speaking, if I did a 50% water change, then should my nitrates not drop by 50 points?


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## carmenh (Dec 20, 2009)

There's an interesting explanation at 
http://www.fishyou.com/fish-nitrates-water.php


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## carmenh (Dec 20, 2009)

Definitely check the filter, and around the base of the plants. (You have to be careful vacuuming around plants, but need to do at least the surface of the gravel to remove and gunk that gets wrapped around stems.) When you do water changes, do you remove the lid? When I had my heavily planted 90g, any fatalities seemed to end up at the back corner, under the light, so unless I inspected with the lid off or water level low, they'd be missed.
I just don't see how the rise could be sudden if something isn't rotting...


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## dinop (Jan 31, 2010)

Could a plant have caused this?

I did have a plant I purchased that after reading here discovered was not an aquatic plant. I have since them removed it.


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## carmenh (Dec 20, 2009)

I *think* anything decomposing, plant or animal, will release ammonia, which, in a mature, cycled tank will end up as nitrate. If the plant's now out, I would do a series of water changes (or a large one as directed in the link I sent) and then measure again, and regularly for the next couple of weeks. Be sure you don't vacuum too much or change out your filters at the same time as the huge w/c...you don't want to cause a mini-cycle and and up with ammonia or nitrite instead...


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## dinop (Jan 31, 2010)

So can high No3 be the result of too many fish?

My wife purchased 20 neons for my birthday - this could be the cause of increased bio load?

Generally speaking, what would be considered a moderate/light bioload on a 90 gallon tank?


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## 1dime (Mar 6, 2009)

I can't figure out what caused the spike.. but what you can do is add more *thriving* plants fit for your setup and it can help reduce nitrates


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## carmenh (Dec 20, 2009)

Definitely any increase in bioload will increase ammonia=nitrite=nitrate but 30-40 tiny fish should be fine in a 90g if you're keeping up the water changes. If the suddenly increased bioload was more than your bacteria could handle, you'd be seeing ammo or nitrite, not nitrate. Like I said, my instinct would be to step up the water changes/vacuuming/filter rinsing. Then test again... If that doesn't clear it up, I'm at a loss, sorry!


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## 1dime (Mar 6, 2009)

carmenh said:


> 30-40 tiny fish should be fine in a 90g if you're keeping up the water changes.


that's what i figured.. unless the tank is new


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## carmenh (Dec 20, 2009)

But if it was a new tank issue, it would be showing ammonia and/or nitrite, not nitrate...nitrate is either added by accident (ferts, etc) or the by-product of bacteria "eating" the bad stuff...



1dime said:


> that's what i figured.. unless the tank is new


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## dinop (Jan 31, 2010)

I do give my plants. Food - maybe that could be it?


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## carmenh (Dec 20, 2009)

Yes, definitely, ferts can be causing it! If you post what exact type, perhaps others can help? Specific requirements of plants with co2 supplementation is not my forte, I always kind of wing it


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