It should not be a problem to keep them in your tank, especially when there is plenty of hiding place.
Rams may "tidy" up their surrounding as they are open spawners. However, for most of the other Apistogramma species, they prefer a small cave. If you have space somewhere, tuck a little PVC pipe amongst the base of the drift wood and they will be happy.
However, don't expect to see them too often during breeding season.
Cheers,
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