Strange water chemistry question

[rBlair]

I've had my 75 gal going for about 4 months now. I added a Rose Bubble tip about 4 weeks ago and it was doing fine. Wednesday I fed it and Thursday I did a water change.

Friday, the BTA shriveled up turning inward (not out exposing the mouth) and all the tentacles disappeared.

I had no idea what was wrong, water parameters are all good in the tank when I tested it this weekend (ammonia, nitrites, nitrates, ph, calcium)

Then I went to do a water change in my qt tank and something told me to test the new water, the nitrites are off the chart. I held back some RO/DI water from the same run in case I needed to dilute the salt, tested that and its fine.

I made a new bucket of water and it tested fine

the only thing I can think of was that I had made the new salt water a couple days prior and did not get to use it until Thursday. Would that have caused the nitrites to spike?

 

[Shewillbemine]

You registered high nitrites on newly mixed water that was NOT put in the display or QT yet?

 

[rBlair]

correct, the water was run through the RO/DI system Tuesday, mixed with salt and let age till I added it to the DT and QT tanks

tested a second time to confirm. Ammonia and Nitrates were both 0

 

[jml1149]

What test kit are you using? API is worthless for nitrate.

 

[Shewillbemine]

The most likely culprit was a faulty/misread test. Salt mix should not have done that, especially if you made another batch from the same bag and it came out clean.

Other guesses would be the bucket you're storing it in or any other ways the water could've come in contact with human or animal waste. Of course that doesn't sound very likely here.

Like I said, probably a bad test.

 

[rBlair]

test is APi

I did do a second test from that same mix and had same results. Then tested the new batch and it was fine.

tested both the DT and the QT, again both fine.

guess it was something related to the water sitting in the bucket and I'll never know what but I will be testing every batch before I use it from now on

thanks all - glad it wasn't a "everybody knows not to do that" kind of thing