Need lend a hand next to a fish outcome?

I have a betta that has been suffering from popeye. Although I own been treating him with the medicine he dosn't look much better & I would say-so is probebly on his way out. When the time comes I want to move from just a small bowl to a small tank perhaps with a filter and try something other then a betta. I know betta's are more tropical fish & I keep my house pretty chilly during the winter. My thought is a smaller desktop type cistern with a built in filter and maybe a few (2-4 ) colder sea fish. I have not heard or read much good roughly speaking the acrylic tanks that scratch so easy. I'm probebly thinking something no bigger next 15 gal. as I want it to sit on my desk. Am open to suggestions from all you fish owners
Rosy red minnows, white cloud mountain minnows, zebra danios, dojo loaches, and mosquito fish are fish that stay small enough for a 10 to 15 gallon cistern and don't need a heater. Goldfish, while cool water fish, capture too large for your tank size limitations.
Depending on how low your temperature falls some species of tetra can do ably in water in the low 70's, soaring 60's.
A good fish that can be housed in a 15 gallon coldwater that's low continuation is White Cloud Mountain Minnows. You could keep a school of 6-7 in within pretty well.

Popeye is cureable and even if the fish keeps a popped eye, he can live a common life. A heated tank and good hose quality are key to curing popeye.

Acrylic does scratch straightforward, but it's lighter and has better viewing quality.
Answers:    Cold water fish are dignified maintenance when It comes to cleaning. You may want to consider using an aquarium heater. They are not very expensive (some can be found for lower than $10) You set the knob to the desired heat and your done. A little stick on thermometer is a good idea, a moment ago to be sure the temp is where you want it. Now you can still have colorful tropical fish. Guppies are attractive and reasonably priced. Good Luck
i recommed fresh water fish because they do live a vveeerrryyy long time. you just need to be up for the hassle of cleaning it regularly. goldfish are not a well brought-up choice. from experience... they dont live long.

hope it helps! and good luck!
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