Welcome Knig6. The female will die if left with the male betta. Even if you have no other bowls or tanks, you can go into the kitchen and get the biggest mixing bowl to keep the female in. As said earlier, the water will need to be changed quite often just like you do for the male's bowl.
You mentioned goldfish earlier so you need to know this. The cheap goldfish that are called comets or sometimes even called feeders will grow to over a foot long and be too big for anything less than about a 30 gallon tank. If you wanted 2 in the same tank, start looking at least to a 40 gallon tank. Some of the fancy goldfish don't get quite as big so you might get away with one in a 20 gallon. Goldfish are not suitable companions to tropicals because they like their water cooler than most tropicals.
Angels like a tall tank because they get quite large and are not long but tall fish. The general recommendation is not less than 18 inches, 45cm, deep. That makes many of the smaller tanks, including your new 20 gallon, too short for an adult angel.
If I were a new fish hobbyist like you I would check my local water supply.
If it is hard water with a pH over 7.0, check into the common livebearers like mollies, platies, guppies, endlers and swordtails. Many of them come in a variety of colors and can be kept in a well maintained small tank like a 20 gallon.
If you have tap water that is fairly soft, check out the smaller tetras. Again, there is a good variety of fish that are only 3 cm or less as adults but that prefer low pH and soft water. Rasboras are very flexible in terms of water and can be easily kept in hard or soft water.
Please start the cycle on your new filter and come back to discuss both your cycle progress and possible stockings once you know more about what kind of water you have and what you like in the way of fish. The best way I can think of to get a good stocking is to find out the water type you have, go to the local fish shop, LFS, write down the names of several fish that you really find attractive and then come back with the list and ask us about what you have found. With the water type in hand, we can probably help pick out the fish likely to do well in your water and likely to do well with each other.
You mentioned goldfish earlier so you need to know this. The cheap goldfish that are called comets or sometimes even called feeders will grow to over a foot long and be too big for anything less than about a 30 gallon tank. If you wanted 2 in the same tank, start looking at least to a 40 gallon tank. Some of the fancy goldfish don't get quite as big so you might get away with one in a 20 gallon. Goldfish are not suitable companions to tropicals because they like their water cooler than most tropicals.
Angels like a tall tank because they get quite large and are not long but tall fish. The general recommendation is not less than 18 inches, 45cm, deep. That makes many of the smaller tanks, including your new 20 gallon, too short for an adult angel.
If I were a new fish hobbyist like you I would check my local water supply.
If it is hard water with a pH over 7.0, check into the common livebearers like mollies, platies, guppies, endlers and swordtails. Many of them come in a variety of colors and can be kept in a well maintained small tank like a 20 gallon.
If you have tap water that is fairly soft, check out the smaller tetras. Again, there is a good variety of fish that are only 3 cm or less as adults but that prefer low pH and soft water. Rasboras are very flexible in terms of water and can be easily kept in hard or soft water.
Please start the cycle on your new filter and come back to discuss both your cycle progress and possible stockings once you know more about what kind of water you have and what you like in the way of fish. The best way I can think of to get a good stocking is to find out the water type you have, go to the local fish shop, LFS, write down the names of several fish that you really find attractive and then come back with the list and ask us about what you have found. With the water type in hand, we can probably help pick out the fish likely to do well in your water and likely to do well with each other.
