Ok, first off your tank is so overstocked FACT?! Doesnt matter what people say, it is lol?! Id put money on that your nitrate level is constantly high unless your performing w/c's like everyday or something?! Secondly, ive seen blood parrots that would be to big to even turn around in a 55g (which i think is a 200 litre or roughly a 46g in europe!) So why would you wana buy a catfish or a large bottom dwelling fish?! Dont wana sound harsh here but you'd probably wana consider buying a larger tank or re-home most of the fish!!!
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