Sump filters, also called trickle filters or wet-drys, are arguably one of the most efficient filtration systems you can employ on your cichlid tank. In fact, they’re so popular, many aquarists make their own using a small fish tank (10g is popular), plastic tubs, or other similar containers. These types of filters are also manufactured (e.g., Eshopps, Aquarium Life Support Sytems, CPR). I won’t go into the details of a good sump-based filter or the technical differences between a simple sump and a wet-dry because that information is readily available on the Web.
However, if you’re using a sump-type filter and you want a change, say to a large canister filter due to noise, water evaporation, or some other reason, don’t fret. If you have a pre-drilled tank with an overflow or two, that’s not a problem either. You can connect your overflow hoses to a canister or canisters. In fact, I have a 75g tank with a corner overflow that I used to filter with an Aquarium Life Support Systems model P1000 wet-dry (no longer made). A few years ago, I decided to take that system down and install a canister.
The photo below shows one of my canisters on my 75g tank connected to the overflow holes in the bottom of the tank (left). Also, notice the reducers that I’ve used to “step down” the hose diameters so I can connect the Eheim canister quick-release values (right).