Hey everyone, I've been in the freshwater world for about 8 years now. I've tried alot of strange setups, and tried to experiment with alot of different biotopes etc. Now, since i know some of you people have predatory saltwater fish that are really big, that might eat small fish, i got a little tip for you. Setup a cheap 50 gallon tank, fill it with guppies (Prefferably ALL brown guppies. In my experience, these have some of the hardy genes like wild caught guppies, which can tolerate pretty much anything. The colored once are little more inbred, and some of them have horrible genes and just bad stuff). What i would do, is get about 4 males. Then get about 6 guppy females per male. Yes, its insane, but they love it. They will breed every single day, and after a month, you'll see small guppy fry in your tank everyday. These guppy fry are healthy, and you can chose to do like me: Which is setting up a nano tank for them to grow up in, or, as i did in the past. Feed them to your bigger fish. I got african cichlids, and these guys devour guppy fry like crazy, and they love it. Live food is just the best. So, i tried to feed my damsel with guppy fry, and he is crazy, he just ate them like crazy. So, why do you wanna feed live guppy fry? Well, your fish needs to get some live food once in a while, whether its brine shrimp, mosquito larvae or krill. But was it really important, is that you give them some live food, that can give some good nutrition. As you we all know, brine shrimp has a pretty low nutritional value, compared to many other foods. Guppy fry however, are highly nutritional, and will give great nutrients for your big fish. And, think about it like this: You've bred them yourself, there are no disease or parasitic stuff. And, you will get maximum health out of your guppy fry, because you know that there are no bad genetics, or any sort of inbreeding involved. Aswell as that, you can grow them to different sizes in seperate guppy tanks, and feed them to different sizes of fish. Man, even my aquatic frogs love guppy fry. Now, probably alot of people are gonna be like "That is so sad, why would you ever feed those cute little fish to those big ones?". But, i can tell ya, they will get alot more happy if you feed them some sort of small fish, and guppies are a great choice. I feed my african cichlids weekly with guppy fry. Believe it or not, it does boost their health, and it makes them feel alot better, because they feel like they are in the nature. Good luck!