Any suggestions? Most of the fish in my aquarium are hardy.
A little bit more info is required to make a suggestion such as tank size and the fish already in the tank. However I would not recommend using a fish as a warning symbol of when water quality has begun to deteriorate. Instead I would recommend using a testing kit to prevent unnecessary stress on a fish.
That statement really worries me. I think a quality test kit would be much better than using a fish to test water quality don't you.
The only fish that comes to mind that can be used as a "gauge" of water quality is Hemigrammus bleheri ( Rummy- nose tetra), it is also known as the aquarium canary as its nose will turn pale if there are any problems with the water parameters.
Your best bet or safeguard against declining water quality is scheduled maintenance program ( water changed bi-weekly, weekly, etc... depending on the bio-load of the fish you keep, stocking density, and if you have a heavily planted tank.
I think it would be cruel to use a living feeling creature as a test kit replacement. Just change the water regularly, don't overfeed or overstock. Then you will not have water quality issues, and no fish will be put under unnecessary stress.
I think we are jumping to conclusions if we assume that the OP was referring to using a sensitive fish as the only indicator of declining water quality. I didn't see that he /she posted that that was the intent. I have Hemigrammus bleheri in my discus tank, I do three 50% water changes a week to keep their water pristine, but my Rummy's are a safeguard to let me know of any issues that may occur despite my best efforts.
Simply take care the waterconditions don't go worse.
I do have an API freshwater test kit so don't worry. I also do weekly water changes and keep my parameters in check. I just want a fish to be able to gauge sudden water changes when they do occur as I can't be testing the water every three minutes right?
Of course I do see it cruel if fish are the ones responsible for keeping water quality in check. I am also planning on adding a few more Rummy Tetras so thanks to @Discusluv for not jumping to conclusions and understanding my predicament.
Sorry for jumping to conclusions, I misunderstood the question. I get it now, and rummynose tetras will work well for what you want
agree with Rummynose and everyone's concerns.
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