1. First decide what is best for your child. You really have two major options as far as fish are concerned: a couple of fancy goldfish or one betta. These would be the easiest and the showiest of the fish that a child could take care of for themselves with basic instructions. 2. Forget about all the fancy appartus for your small tank 3. Fill the tank with tap water and let it set for a couple of days. Also fill up a gallon jar with tap water that will be used to replace water in the tank. 4. Put the tank in a warm room but not in front of a window but be sure the area is well lit so your child can enjoy the fish. 5. Take your daughter and go to a local pet store and have her look at the gold fish and at a betta to see what she would like between the two. Tell her that if she is interested in any of the other fish that she needs to learn how to keep the two choices first as you would have to buy a much larger tank for them, if she asks about the other fish she would see. 6. Be sure to buy the appropriate fish food for either the goldfish or for the betta. 7. While you do not need to get one you may want to look at an aerator. Talk to the clerk at the store about one suitable for a small tank. Needed with the aerator MAY be air tubing and an air stone. 8. Take the fish home and set the bag with the fish in the tank of water and let it set for 20 minutes before opening and letting the fish out. 9. Give the fish a couple of hours to adjust to the new tank. If they look happy then take a pinch of food (amount held between your thumb and first finger) and drop into the tank. Do this only once a day. Every three to four or five days remove 1 gallon of the water from the tank and add in slowly the water that has been sitting nearby. Dump the old water out into your flower beds and add fresh water into the gallon jar to set until the next replenishing. This is a basic set up without all the fancy stuff and all the hassle of gravel, filters, and plants that make it just too much of a chore for a child to have to deal with. Keeping it relatively simple will give your daughter a good chance of learning and enjoying the experience. To help you may want to sign onto TetraCare. Check the link. Here is a link that might be useful: TetraCare

Hi no more fishin the tank. With what you have now, problems will arise. No red-tailed black shark either. They get to large for your tank and they are not the best choice for a community tank.And as for the 1 inch per gallon, that does not work either, for example a 2 inch gourami has a much bigger body than a 2 inch molly yes you could put 10 mollies in a 20 gal tank but would you put 10 gouramis in the same size tank

I hate math. I measured by big pots again, but mine aren't for permanent, only for growing on when necessary. I measured 14" across the top, 10" across the bottom, and 14" in height. Assuming a radius of six I calculated about 7.3 gallons. I can imagine that being close. The sticker in the pot said capacity was about 1.25 cubic feet, and that conversion to gallons was saying over nine gallons. THAT I don't believe. Of course, I am pretty spatially challenged, too. And stink at math. I am bowing out of this conversation.

How many tubes in each tank? One might be enough for the AVs, or might not, but definitely won't be enough for the succulents. Two might be enough for your succulents, you'll have to judge how they go. The tubes should have some cryptic writing on that will tell you exactly what they are. It will have something like "F20W" or "F20/T12" and a colour line such as "colour54", or "540". It might even say "white" or "cool white". A 20W T12? Probably cool white, but I know they do make them in other temperatures. Compare the tube side by side with an incandescent bulb. A warm white will look similar, a cool white will make the incandescent look quite orange. Or better yet, compare to a known cool white fluorescent. Cool white will look the same, dayling will look blue-ish, and warm white will look orange-ish.