The Puffer Forum

Hi all,

I've just done a water change (about 15%) and when I tested the water I noticed that the nitrites and nitrates are very high. I'm puzzling as to why, the water was tested about a week prior and no problems.

The tank has been set-up about 6 weeks and I've been doing weekly changes of 15%-20%. SG is 1.005 and steady. pH is fine too.

The only thing I can attribute it to is there are a couple of plants in there that are dying. I've left them in there as I plan to get a CO2 fermenter early next week and hope to revive them.

Could they be the problem?

I'm no expert, but I knopw any plants, even as they start to die, they are like a toxic waste plant. Take fish poo, its a bit different and all, but it pollutes a tank enough. Now take something about 1,000 times that size (a dead or dieing plant) and put that rotting into your tank. That definately could be it. But I'd wait to be certian for someone who has more experience.

But until someone else replies, I'd avise you, if you wanna keep those plants, take them outta the tank, setup some kinda temp place for them (a spare tank; bucket) and fill it with tank water and some substrate if its not still potted, and quarentine them until you get them healthy again, or that CO2 in em.

Where there 0 nitrites before? How did you cycle the tank? Have you checked your source water? If your source is 0, get on massive daily or twice daily water changes, and remove the plants.

Like LL says, check the nitrates in your tapwater, if they're normal great, if they're high then adjust water changes accordingly. Bigger or more frequent water changes should get it under control.

What size tank & what fish are in there? SkeptikaL is right. You may have a hard time keeping plants at all in that SG.

Tank was cycled with some danios (before introducing the salt) and some live bacteria from a pet shop. My readings have been fine until this most recent one. They've been done roughly weekly since the first week or two, more regular before that.

Tank is 120l with 2 F8 puffers and 4 Bumblebee Gobies.

The tapwater is fine, no traces at all. I've done a big water change today and will do more over the next couple of days. I've also bought a nitrate/nitrite remover that goes in the filter (bit sceptical of it though.)

Hopefully I'll be able to bring it down before the fish suffer.

Oh, and I took the plants out. Although they only had a couple of brown leaves the roots seem to have rotted completely and left my sand black! Almost definitely the plants causing the problem then!!!!

What actually are the results of your tests?

kjharve wrote:Tank was cycled with some danios (before introducing the salt) and some live bacteria from a pet shop.

You shouldn't cycle with fish. If you do a search here, there's a ton of posts (as well as at least one article) on fishless cycling.

Which "live bacteria" did you use? If it was Biospira, then it works and the danios would have been in no danger. If it was anything else, it wasn't "live" and is basically worthless.