High ammonia, 0 nitrites in a seven year old tank?

[Runsoncoffee]

I’ve got a 75 gallon tank, the tank itself is only a year or 2 old, but everything (substrate, decor) that went into it during set up has been with me for 7 years. I’ve gone over to having the tank planted, and it’s been very healthy.
I tested that water last week to see if the tank needed to be cleaned (which it almost never does because of the plants) and the ammonia was super high. I cleaned it right there, and did the same the next week. This week I tested the water and the ammonia is still super high, but the nitrites are reading a 0.

What could cause this? None of my fish are sick, I’ve even gone and dumped out dirty water in the filters, and searched for a potential dead fish (I’ve got SA cichlids and sometimes schooling fish go missing). I’ve got no idea what’s causing this, any help would be appreciated

 

[Aiken Drum]

What are you considering super high ammonia? Have you tested something like bottled water that you know is 0 ammonia to check your test kit is ok?

Things that can cause an ammonia spike. Maybe the fish somehow got overfed (overzealous child? Im talking to you Timothy). Dead fish. Tank or filter maintenance. Maybe the water company did some maintenance and added a ton load of chloramine/chloramine to clean up and you introduced it into your tank with a water change. New fish/increased bioload. There are many things that can cause this. Did you do anything out of the ordinary?

As to why your fish are showing no issues. Ammonia isnt always the health issue you might have been led to believe. Your test doesnt measure ammonia, it measures total ammonia nitrogen (TAN). This is free ammonia + ammonium. Its only the free ammonia that is harmful (at least mostly) and ammonium is nowhere near as toxic. The proportion of free ammonia to ammonium is pH and temperature dependant. The higher these are the more of your TAN will be free ammonia. Depending on how much TAN you have and what your pH is, you might not have an issue.

Lets look at 2ppm TAN.

At a water temperature of 24c/75f you would have to have a pH of 7.8 before you are in the red and seeing immediate issues. At pH 7.2 you are green and there will be no toxicity to the TAN.

If your pH is below 7 you will basically have no toxicity from TAN at all in a typical aquarium environment.

 

[Runsoncoffee]

I apologize I don’t remember the specific number,but I’ve got the the tetra fin fresh water master test kit, and the ammonia keeps coming out a dark green.
I haven’t checked the test kit against plain water, but I’ve tested on other tanks I have and don’t have the same issue.
There have been a few deaths, but I’ve pulled all the dead fish out (or there weren’t fish to be found, happens with cichlids). And I’ve done 2 water changes since
It is entirely possible I’m feeding them too much. I’ll clean more and feed less and hope it resolves the issue

 

[gilpi]

I have little knowledge of plants but the water should be changed regularly regardless the plants. Plants alone can not handle the bio load. Of course overfeeding is always a problem as well.

 

[Runsoncoffee]

The plants eat the nitrites, so it is sort of a self sustaining thing. It was to the point where I could change the water every 3 weeks and the water quality was fantastic! It’s entirely possible I’m over feeding. I’ve been kinda tossing in a pinch and walking away instead of taking the time to watch every one eat and putting tiny bits at a time.
Im starting to feed less and watch to make sure the amount is correct, as well as just cleaning more until this is sorted out.
But partially answering my own question, with the plants eating the nitrites, and me most likely over feeding, that would explain why the nitrites were low(plants doing there thing) and the ammonia being high (me not paying attention)! [emoji23]?* feel kinda dumb now……it’s for sure gonna get fixed [emoji23]

 

[Aiken Drum]

Plants dont eat nitrite. They do nothing for nitrite. They will take up some ammonia and nitrate but not nitrite.

While this may help you control nitrate there are other reasons for water changes. Do your regular water maintenance.

 

[Runsoncoffee]

Plants dont eat nitrite. They do nothing for nitrite. They will take up some ammonia and nitrate but not nitrite.

While this may help you control nitrate there are other reasons for water changes. Do your regular water maintenance.

My apologies I get confused between the nitrates and nitrites sometimes. I’m for sure doing the regular water maintenance! I love my fish, and and I want the best for them. I’m just a college student, and so having the plants to help out with water quality has been a God sent. But I’ve obviously been slacking, which is going to change. Thanks everyone for the help!

 

[Aiken Drum]

Sorry i didnt pick up on the low water change frequency, that's why a community forum is great. One person might up something that another isnt.

What could be happening is known as old tank syndrome. Water change frequency goes down as people get more comfortable, this causes the water to lose carbonate hardness over time. Carbonate hardness is required for the nitrogen cycle to nitrify ammonia into nitrate. If carbonate hardness isnt sufficiently replenished through your water changes it gradually gets used up over time. Once its gone your cycle loses its ability to consume ammonia. This is one of the other reasons for water changes. It isnt just about removing waste, there are also essential components in your water that need replenishing.

I would always aim to change a small amount of water weekly even if you think its not needed. You might be good with a lightly stocked tank in a heavily planted tank, but this isnt often the case.

 

[Runsoncoffee]

Sorry i didnt pick up on the low water change frequency, that's why a community forum is great. One person might up something that another isnt.

What could be happening is known as old tank syndrome. Water change frequency goes down as people get more comfortable, this causes the water to lose carbonate hardness over time. Carbonate hardness is required for the nitrogen cycle to nitrify ammonia into nitrate. If carbonate hardness isnt sufficiently replenished through your water changes it gradually gets used up over time. Once its gone your cycle loses its ability to consume ammonia. This is one of the other reasons for water changes. It isnt just about removing waste, there are also essential components in your water that need replenishing.

I would always aim to change a small amount of water weekly even if you think its not needed. You might be good with a lightly stocked tank in a heavily planted tank, but this isnt often the case.

This was actually something I was concerned about. I haven’t done any research on old tank syndrome, but was worried that this might be it. Water changes are going to be done more regularly now
Thank you

 

[Aiken Drum]

Just be careful not to change too much too quickly. As per my post about ammonia toxicity, pH effects how toxic your ammonia is.

The other thing losing carbonate hardness does is it removes your waters capacity to buffer acid. Fish respiration acidifies the water and with low buffering this causes a drop on pH. The lower pH will detoxify your ammonia. But, do a big water change, your KH goes up, so does your pH and the ammonia gets more toxic immediately.

So, if you plan on upping the water changes, dont suddenly go all in with a big water change. Do a small one, same again the following day. Then a bigger one a few days later. Make small gradual changes to your infrequent schedule.

 

[Runsoncoffee]

Just be careful not to change too much too quickly. As per my post about ammonia toxicity, pH effects how toxic your ammonia is.

The other thing losing carbonate hardness does is it removes your waters capacity to buffer acid. Fish respiration acidifies the water and with low buffering this causes a drop on pH. The lower pH will detoxify your ammonia. But, do a big water change, your KH goes up, so does your pH and the ammonia gets more toxic immediately.

So, if you plan on upping the water changes, dont suddenly go all in with a big water change. Do a small one, same again the following day. Then a bigger one a few days later. Make small gradual changes to your infrequent schedule.

Will do! Will most likely change 10 gallons each day for the next few days. Did over. 50% water change last week because I didn’t realize it was old tank syndrome, I just saw suuuper high ammonia and panicked. So gonna go super duper slow