Ok I deal mainly in bettas but I want to start moving into salt water, and bigger fresh fish. However I am not so knowledgeable about all other breeds. I have to admit I did a very super stupid newbie thing. I bought my wife fresh water stock, with like bare mininum aquarium parts. I have her small guys in a 2.5 gallon jug by a space heater, no air stone. And the "shark" which I forget what type it is, is in his own like 2.5 tank with a cheap filter and airstone. However the temp of the water is off obviously because I don't have a heater. Though the "shark" will stay in this 2.5 tank, should I get a small cheap heater for him? Also when I was acclimating him, he did something odd. He was floating tail down and not moving. He would be active and then just float and his eyes looked a bit bulgey, it freaked me out and now I think he is a bit more acclimated, but if there is anything else I can do please let me know. Also if someone can tell me the type of "shark" he is, he is silver and black, and has whiskers, the pet shop is closed now so I cant go back to look. I also hardly ever buy from pet shops but this one has good fish and a good rep. Do you think the little guys (gups and tets) can survive a while, while I get the tank set up and put in some algae stim?
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