hi. i have 2 questions that are completely unrelated to eachother.
1. do fish get old and frail like humans? i have had a honey gourami for years over the last few weeks he's got really skinny and lays on the bottom mostly only coming up occasionally for air (which seems a struggle)
Fish do get old, yes, though you might try to do other things to help your fish just in case its something else, though it sounds like he had a good run.
Don't know about the impeller, though I know people do it on filters sometimes.
depends on how small the tank is and how strong the powerhead is ive been told.. some are flow adjustable.. gouramis do live for a few years, but something could be wrong with him like a disease or something like that..
Honey gouramis live for about five to eight years on average, don't know if your's was already old when you bought him from the LFS or it has a possible disease. More info would be appreciated.
I don't know about question two, but I know that some filters are designed so that the intake and power can be varied.
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