oxydoras niger ripsaw catfish

Anyone have experience with OXYDORAS NIGER, PTEDORAS GRANULOSUS and MEGADOLORAS IRWINI? I've kept my granulosus for about 3 years starting from 4 inch and now he is 8inches, however he was 8inches for the past year and a half. He is in a community tank where I give live feeders weekly which he...

I just bought 4" OxyN last week and is it possible that these fishes are farmed? Since farmed fish are runt, I'm afraid it will never exceed more than 1'. Or does it just like RTC, still can grow to huge sizes even though its farmed?