I have a feeling that either A) your tank maybe going through a mini cycle since you said you cleaned your filters or B) your tank is over-stocked and your filter can't handle the bio-load...
just orderd overnight shipment for testkit plus the stress zyme and some stress coat as for filter bioload I am going to be replaceing the carbon pads(I use cut eheim carbon pad pieces)once I get everything and also am going to be adding plants(swords and telanthera) as well as frogbit to aid in filteration altho I believe it is mini cycle since filter was so dirty and im adding more air pumps for more oxegen but my concern is wat should I do for now as I said only bottom feeders are acting strange the hatchetfish and tetras are fine I did water change earlier and im keeping my emergency air pump on and not going to feed the corys keep digging as well as breathing heavy and plec keeps fanning should everything be okay till shipment comes?