There are many bad reviews on this product and honestly I think people expected more and didn't bother to read the description of this product. Yes it is small but not too small if you only have 1 maybe 2 goldfish or a rooster. For goldfish, this is the same as your regular aquarium, and goldfish are hardy fish that do well in such an environment. For Bettas, as long as your home doesn't stay below 70 degrees, you're fine without a water heater. Bettas are constantly kept in flower pots with plants growing from above. One or two other small fish that don't require a water heater will also work. With that said, just read the specs for this tank and do your homework on what fish do best in small tanks and move on. It worked great for a goldfish that I no longer wanted in my large tank and that nobody could take.
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