SIOUX CITY | Starting up a freshwater aquarium can be an exciting -- albeit confusing -- endeavor when the fish enthusiast realizes all the options available.
There are four main types of freshwater fish available at most pet retailers. They are community, semi-aggressive, cichlids and goldfish and they have different temperaments and requirements that make it impossible to cherry-pick random fish for an aquarium.
The most important factor in determining which type of fish to get is tank size. Any tank below 20 gallons should only be used for community fish and some semi-aggressives, said PetSmart pet care leader Kari Cheever.
“If you want cichlids, goldfish or even certain semi-aggressives, you have to start with a bigger tank because they’ll get pretty big,” she said.
Most community fish stay only a couple inches long, while cichlids and goldfish reach between 6 inches and over a foot long. There are several semi-aggressives that stay small but, as their name would suggest, they tend to nip at the fins of the more docile community fish. It’s safer to keep semi-aggressives together and community fish together, separately.
For the larger fish, cichlids and goldfish need to be kept in large tanks with their own kind. Goldfish tend to be more docile and require cooler water temperature while cichlids are aggressive and like warmer water, which makes them incompatible.
Cheever noted that all goldfish require aquariums and there are no goldfish that can live in bowls.
“Goldfish should never go in bowls,” she said. “If someone wants an easy fish that can go in a bowl, go with a betta because they don’t need special air pumps or filters.”
Goldfish are noted for not living very long, but that’s due to improper housing. Goldfish kept in aquariums can live up to 20 years.
Cheever noted that a smaller tank doesn’t mean easier care. In fact, the opposite is true.
“Ten gallon tanks are actually one of the harder ones to keep because if something happens, it affects the water quickly and can kill off the fish right away,” she said. “If you start off with something larger, you can have time to catch problems before they take over.”
Choose a sturdy, level surface near power outlets to set up the aquarium. With water, gravel and the weight of the tank, each gallon is estimated to weigh about 10 pounds. So a 20-gallon tank would end up weighing about 200 pounds once full, Cheever said. Putting that on an uneven surface can cause damage to the seals of the tank resulting in leaks.
Overstocking a tank is a common problem that can affect the water quality and health of the fish. For community and semi-aggressive fish, there should be 1 gallon of water for every inch of fish. For cichlids and goldfish, there should be 2 gallons of water for every inch of fish.
It's also important to set up the tank at least a week before adding any fish as beneficial bacteria need to build up and a nitrogen cycle needs to complete. This is why the first group of fish in a new aquarium frequently die within a day of adding them.
Despite the guidelines, there are never guarantees when it comes to animals, Cheever said.
"There is no 100 percent what will happen every time," she said. "We can only tell you what is most likely to happen."