What do y'all think about bubble eyes and pea gravel? If  I can find the money to start up a 20 for two bubble eyes, I will, but in the mean time I'm still looking for a good deal on a 20 for my moors. That ten won't last the two another month or so! Anyways, what's your opinion on those bubbles and gravel? I think it should be okay, and in my bubbly plans are a canister filter. I'm guessing that would be least likely to suck them in, and I also have heard that undergravel filters are crappy. Never had one for that reason. Also, would you say about a newbie having bubble eyes? I'm open to other suggestions, but no comets or a common. I can't have any tanks bigger than 20 'cause of where I live. And, cats are living outside, so no ponds.  

That's great advise Nossie! I am such an impulse buyer, and I take pity on the poor animals that are couped up... but I know I can only take care of so many. When I buy my own home it will be different but at the moment my partner and I are still just renting which minimises the amount of animals I can have.

hailsontherocks: Oh yeah. I'm right there, right now! 83 gallon, a betta bowl and a small 8 gallon is all I can fit in here :/ But oh, how I'd want a guinea pig or a little doggie! D':

I agree with Nossie, handle getting your current fish a bigger home before you tackle a new set up. But when you do get ready, let me make a few suggestions.

Canister filters are great. Very powerful and efficient. I have used them for years and love them. But they do tend to have a strong intake, as do hang on power filters. Putting  sponge filter over the intake will help to weaken the water draw, but they get clocked fast and they catch debris before the filter even has a chance to.
Undergravel filters are as you say, "crappy". What you have to remember with UG is that it is old school. It was one of the first filtration designs to be used. The way they work is that they draw the water through the gravel, catching any debris on the gravel as well as oxygenating the gravel. This allows your gravel to function as a mechanical and biological filter. Downfall is that they catch all of the uneaten food and fish waste in the gravel and have to be vacuumed vigorously. 
My recommendation is this...
Use an undergravel filter plate (or make your own out of light diffusing paneling "eggcrate" and window screen) and a canister filter.
Connect the canister filter intake to a lift tube from the UG. Then the canister will draw its water from under the gravel. That way there is no suction at all for the fish to get caught in. Use roundish, smooth pebbles for your substrate, about marble size. The bigger pebbles will allow more debris to pass through so that the canister catches it instead of the gravel.
By doing this you will provide a tank with a gentle flow to the intake. Your fish will be safe and you will still have the great filtering capabilities of the canister.
This can also be done with the hang on power filter but it may be a bit trickier to work out the logistics. Either way will take a bit of problem solving skills to get set up, but it is not that hard to figure out. Oh... and you may have to make a trip to Home Depot.