No. The tank is not large enough to house two female bettas. The basic fish keeping rule is "1 inch of fish needs 1 Gallon of water". A female Betta grows to around 1.5 inches so you would need at least a 3 gallon tank to house the 2 Bettas properly.
Yes with a divider but without they will kill each other.
of course, but only keep one male in there at a time unless you have a divider. They say a one-gallon is big enough but my personal opinion is a 5+
ONLY if they're either two females - or a male * female. Two males housed together WILL fight.
The fish are not bad together. But way to many fish for a ten gallon tank. You put one fish for every gallon. They will probly do fine but you will have to clean more.
NO! you will need at least 5 gallon for those
Yes.
Absolutely not. One oscar fish needs at least a 75 gallon (US) tank on it's own as they can grow up to a foot in size. If you have already bought the fish, please return it to the store and let them know that you do not have a large enough aquarium for it. You are best to use the 1 gallon bowl as a change bowl, and instead spend a bit of money on a betta tank kit for one betta fish, or 2 if you get one with a divider as they cannot be in the same tank together.
First, buy a 10 gallon glass tank. Second, buy a wire mesh divider at a pet store. Third, install the divider. Fourth, put one gerbil in one side and the other on the other side. Leave them there for about 3 - 4 days. Last, wear rubber gloves and carefully remove the divider, letting them smell each other. If they fight, break them apart and divide them for a couple more days. Repeat until necessary.
no
ONLY if they're male and female. If you put two males together - they will fight for dominance, possibly resulting in serious injury to one or both !
This is a BIG NO NO!! Bettas need at least 2.5 gallons of water to themselves, and if you put a male and a female together, it will most likely result with you have two dead bettas. Keep your boy and girl in separate 2.5 gallon heated tanks.
yes they can but they have to be in a ten gallon tank or 17 gallon you can fit one inch of a fish per gallon