Nitrite testing

[Spud2564]

How often should we test for nitrites (there are currently no fish in the tank- just plants.)
Is there anything else I should test for before adding Spud the Potato Puffer?

 

[Blinky]

Are you doing a fishless cycle? If so, I'd test the nitrite levels daily - when you see NO2 levels drop off and NO3 levels start to rise, you know you're nearing the end of the cycle.

 

[Spud2564]

We are doing a fishless cycle but we are adding a pleco at the weekend just to make sure. Should I test after we get the pleco? Last time we tested we were in the clear- nitrite wise.

 

[Blinky]

Yep, I would. Sometimes when you're just finished a cycle and something changes in the tank there will be a spike of ammonia or nitrite, so it's a good idea to test just in case.

 

[happychem]

Whoa! Hold on now! Are you doing a fishless cycle or not? You cannot] add fish during a fishless cycle, unless you change all the water and basically start fresh. Adding a fish without doing this would do worse damage than a fishy cycle.

On that note, you can't really keep plants very well during a fishless cycle either. It's a recipe for algae.

Testing NO2 once or twice weekly should be sufficient. When NO2 and NH3 both drop to 0ppm in 24 hours following the NH3 dose, then it's safe to add fish.

 

[Spud2564]

We aren't using ammonia, w'ere using some stress zyme stuff.

 

[happychem]

Then you aren't fishless cycling.

 

[Blinky]

I got the impression you were just ending a fishless cycle, and the fish were being added on the weekend because the cycle would be complete then. If you're not using ammonia, then the tank's not cycling - the bacteria you want to cultivate on the filter media use ammonia and nitrite as food sources, and without it they won't develop. There is a lot of informaton here on the AC website about how to fishless cycle, it's really important to read up and make sure it gets done properly or you could lose your fish.
I'd hold off on adding a pleco and start doing a proper cycle - it will take a few weeks, but it will save you a HUGE headache if you do it right from the start.

 

[liuj1]

What if the nitrate level is ridiculously high, but the nitrite levels are moderate but steady?

 

[daveedka]

The only good nitrite level really is 0 ppm, anything else can and will harm your fish. The extent of the harm is largely based on the level of nitrite, but even with tough fish harm is still done. the nitrate level being high is probably a result of the stress zyme. If it supposedly has bacteria in it, any that happen to still be alive when you add it, will die and become pollution. most of them will be dead before they leave the bottle, so they are already pollution when added. If stress zyme doesn't claim to have bacteria in it, then I don't know what would raise the Nitrate, but let us know everything you have added to the tank, and someone here will figure it out.
Either way nitrate can be removed via water changes, and low levels of nitrate won't harm you fish. Most of us reccomend nitrate below 20ppm, some folks allow them as high as 40ppm.
dave