New fish; first time fish owner; Molly fish; tanks

Question

Fish  

Actual Tank   Hi. My roommate and I recently purchased 2 fish this morning. It was very spur of the moment kind of thing and I am the one having to set up the tank and fish. I have absolutely no idea what I'm doing. The fish we got are a Dalmatian Lyretail Molly (poecilia latipinna) and a Silver Molly (poecila sphenops). In doing some research, I keep getting different recommended tank sizes, temperatures, and water hardness. As for the tank sizes, I keep getting anywhere from 10-30 gallons. The size tank we purchased is a 5.5 gallon tank. Will it be big enough? Also, how can I tell what sex the fish are? Any information you can give me would be greatly appreciated. Thanks for your time.

Answer
The next time do not do impulse buys. Please do research before you buy any living creature.

Google nitrogen cycle. You need to cycle a tank 6-8 weeks BEFORE you get fish. You need to acclimate fish to the tank slowly for 1-2 hours.

Mollies need 25-30 gallon as they can get 5-6 inches in length. They will more then likely die of a spike of ammonia or other water chemistry from being confined in such a small aquarium AND because of the cycling tank. I suggest returning them before their lifespan is shortened or they die.

A 5 gallon tank is only made a single Betta Splenden and some shrimp. That's it.

It looks like the silver and the dalmation at the top are females. I cannot tell the bottom fish.

Mollies prefer a higher temp of 78-82 F and they do need 3+ buddies which you have...just not the appropriate tank size. They need harder water and a higher PH it is recommended that they be kept in brackish as they thrive better. Molly fish are not beginner fish as they are high in water quality demands.

Please return these mollies to the store they will not live long enough or happy before you get a 25-30 gallon for them, do some research on keeping fish, and then once you cycle your 5 gallon for the appropriate amount of time with test strips, buy APPROPRIATE sized fish for your tank.

- Ash