First, "over filtration" does not exist, in the sense of some sort of benefit. Filtration involves keeping the water clear (this is mechanical, and any filter with media of sponge/foam/floss will do this), and keeping it clean (the biological involving bacteria using ammonia/nitrite but it goes beyond this). Provided the tank is biologically balanced with respect to the fish load for the volume, any filter that provides the mechanical is all you really even need if you have plants, and if not then a basic biological filter suited to the tank space. Any larger filter or adding more has absolutely no benefit, and may be detrimental.
Filters control the water movement, and different fish have differing needs for current so this must be factored in. A 29g tank is not likely to have a fish load requiring a canister filter. Fish for this tank will be relatively small, and even a basic sponge filter may be all you need, depending upon the fish species. And live plants factor in too.
