Under gravel filter?

So I had been thinking about getting an under gravel filter but the ones I've seen so far all looked kind of crappy. I was hoping someone could recommend a good one. I was looking at the 12x24 inch ones that are for 20 gallon tanks. Anything would be helpful! Thanks.

Undergravel filters are generally kind of crappy.

To get one to work effectively, first you need gravel, which is not appropriate for most caudates. Then you need a powerhead, which creates a large current, and you need to run the system in reverse, that is, it blows water up through the gravel instead of sucking it down through the gravel. Otherwise you'll just get waste trapped under the plates, which will have to be removed by lifting up the plates (as well as the gravel on top, and any plants you have, etc) and sucking the waste out by means of a turkey baster or something of the sort. That is, if you can get all the waste before it makes a large cloud in your tank. This trapped waste will lead to spikes in ammonia, nitrites and nitrates.

I recommend using a thin layer of sand as a substrate. And in a 20 gallon tank, you can get away with just one hang-on-back type filter or a hang-on-tank mini canister filter. This system is much easier to maintain and much healthier than using an undergravel filter.

Hmm, I had a bad experience with sand and even if the sand was okay, I don't think I would ever use it again (it would just make me worried and stressed). I was going to use larger 2 inch rocks and thought the gravel filter may be easier then cleaning all those rocks every 2 months (this is what is recommended right?). But according to the prices I've seen and the quality of under gravel filters, as well as what you've said, it seems like cleaning every 2 months is way easier. Thanks!

Have you read the thread about using slate tiles on the floor bottom? If you don't like sand and gravel/rocks are not recommended, you might want to see the slate tile option or go with bare floor, easy to clean.

Why don't you like sand?

River rocks isn't ideal either. A lot of waste will be trapped in them.

I looked into the slate idea and it seems like it would be a good idea. The more I look at it, the more I seem to like it. Easy to clean too, and that seems to be why I wasn't sure about the rocks! They would be a total pain to clean all the time, with all that debris. The more I think about that, the more I dislike that idea.

Thanks for the help!