Why am I getting nitrite spikes after a water change?

[Tony]

I live in Gatihersbrug as well.. across from the Kentlands. I do 50% water changes on all my rack tanks every 7-8 days and add water straight from the tap via a Python. I dose dechlor (Genesis) right into each tank as I'm filling. I do smaller weekly changes on my bigger tanks the same way.

Never really had any noticable problems, but since I first moved in, haven't been testing water out of the tap much lately.

Joel - that is interesting about the potential of the water works switching up treatments by time of day. Makes sense, just never thought of it before.

 

[hollyfish2000]

Update -- did 10 percent water changes yesterday on both tanks using tap water with appropriate (not excessive) levels of Prime and some additional RO water and the new bucket. I tested both tanks before and immediately after the water change, and then some hours later. The large planted tank remained at 0 ammonia and 0 nitrites and I made sure there was sufficient powerhead movement after the lights went out, so no oxygen deficiency problems. In the other tank, I had a very small amount of nitrite (it went from baby blue to slightly darker blue but nowhere near purple) immediately after the change. That slight darkening was gone by the second test a few hours later. Whew.... So far so good!

 

[YSS]

Very strange. If there is nitrite reading immediately after the water change, there must have been nitrite in the tap water, but you said there wasn't. I am going to test for nitrite in my tank after the water change and see what happens.

 

[hollyfish2000]

No nitrite in the tap. I checked before it went in.

Hey Tony -- I live in the Kentlands. We're neighbors!

 

[YSS]

I did a 20% water change in my discus tank last night and tested nitrite for an hour, but no change in the reading. I use API's Tap Water Conditioner and don't over dose. I used to use Prime, but it got too expensive, and so far I haven't had any issues with the Tap Water Conditioner.