I decided that since nothing but bettas and my original corries and oto are able to stay alive in my 20 long (why???) I'm going to divide it for bettas. I'm going to divide it in 5 sections, each 6" wide x 12" deep x 12" high and about 4 gallons per betta. I'll probably have different substrate in each section depending on the betta's color but it'll be either very fine gravel or sand. The filter is a Penguin 170 or 200 which will need to be baffled but I have a smaller Penguin 110 if I should use that instead. I have a heater and there's a light and hood. I'll use the live plants that I have as well as silk ones. Does all this sound okay?
But the dividers is what I need help with. I've seen all the threads on the homemade ones, so please don't give me links to those, but I need something that doesn't need to be permanently in the tank. In a few years I may decide that I want it as a community tank again and what will I do if there are dividers siliconed in? I'm afraid if I use the homemade, flimsy dividers without securing them they'll let the bettas get to each other and that would be terrible. I need something that I can make myself, is sturdy enough to not move and can be removed at least semi-easily.
Thanks in advance for any help!