Something feels off

[TidalFlow]

My marine tank has been cycled for at least three weeks now, but the ammonia level is still at 0.25 and not dropping. I just set up three new freshwater tanks and ran ammonia tests on all of them - they all came out at 0. I even tested the tap water and it's also at 0. So, where's this ammonia coming from? The tank only has live sand, live rock, some dry rock, and reef salt in it.

[kingrise]

My marine tank has been cycled for at least three weeks now, but the ammonia level is still at 0.25 and not dropping. I just set up three new freshwater tanks and ran ammonia tests on all of them - they all came out at 0. I even tested the tap water and it's also at 0. So, where's this ammonia coming from? The tank only has live sand, live rock, some dry rock, and reef salt in it.

I'm happy to help you out, TidalFlow. So I'm guessing you're a bit stumped about where this ammonia is coming from, huh. Ammonia usually comes from fish waste, but since you don't have any fish in the tank yet, that's probably not the culprit. It can also come from uneaten food, but it doesn't sound like you've been feeding anything in there. Decaying organic matter is another possibility, though. I'm thinking maybe it's something to do with the live rock you've got in the tank.

Those rocks can be home to all sorts of tiny critters and invertebrates that produce waste, and that waste can definitely contribute to ammonia levels. And even if you've got live rock, it's possible that algae is starting to grow in the cracks and crevices, breaking down and releasing ammonia as it goes.

[TidalFlow]

My marine tank has been cycled for at least three weeks now, but the ammonia level is still at 0.25 and not dropping. I just set up three new freshwater tanks and ran ammonia tests on all of them - they all came out at 0. I even tested the tap water and it's also at 0. So, where's this ammonia coming from? The tank only has live sand, live rock, some dry rock, and reef salt in it.

I'm happy to help you out, TidalFlow. So I'm guessing you're a bit stumped about where this ammonia is coming from, huh. Ammonia usually comes from fish waste, but since you don't have any fish in the tank yet, that's probably not the culprit. It can also come from uneaten food, but it doesn't sound like you've been feeding anything in there. Decaying organic matter is another possibility, though. I'm thinking maybe it's something to do with the live rock you've got in the tank.

Those rocks can be home to all sorts of tiny critters and invertebrates that produce waste, and that waste can definitely contribute to ammonia levels. And even if you've got live rock, it's possible that algae is starting to grow in the cracks and crevices, breaking down and releasing ammonia as it goes.

TidalFlow said:

Thanks for the response! I'm still stumped though - I haven't added any fish yet, and I'm not feeding the tank. I'm starting to think it might be the live rock or the live sand. I did rinse the live sand before adding it, but maybe not thoroughly enough? And the live rock - I did a pretty good cleaning on it too, but I guess it's possible something's still in there breaking down. Do you think it's possible the reef salt could be the culprit, or is that unlikely?

[TidalFlow]

Thanks for the insight, I was stumped. I've got some macro algae on the way, hopefully it'll help get my ammonia levels back under control.

[kingrise]

My marine tank has been cycled for at least three weeks now, but the ammonia level is still at 0.25 and not dropping. I just set up three new freshwater tanks and ran ammonia tests on all of them - they all came out at 0. I even tested the tap water and it's also at 0. So, where's this ammonia coming from? The tank only has live sand, live rock, some dry rock, and reef salt in it.

Glad you're on top of it, the mcora algae should definitely help with bringing that ammonia level back down. Dead or dying algae can contribute to the problem, so try to remove any you can see, it might make a difference.

[onyzza]

To confirm the ammonia reading, I'd recommend double-checking with a different test kit - perhaps one from a local fish store. It's also possible that the 'live' sand you added might not be as live as you thought. If it was exposed to high temperatures during shipping or sat on a shelf for too long, the bacteria would have likely died off, essentially turning it into a waste bomb for your tank. In cases like this, it can take a long time to resolve the issue, much longer than if the sand had been in good condition.

If the ammonia reading is indeed accurate, it's just a matter of time. Let the live rock do its thing and work on breaking down that ammonia. Another possibility is that there's been an unusual amount of die-off from the rock, which could be contributing to the elevated ammonia levels.