Hiya guys, hows it going?Anyway, another question from my grandad here, as he has got the first 12 fish in and they have settled in nicely after about 2 weeks, so he now wants to insert some bottom dwellers. Now he is not sure which would be best as he has quite large gravel and loads of spreading plants such as java fern.He likes pleco's but these can grow too large so i suggested something like kuhli (coolie) loach or zebra catfish but only if he is able to change his substrat. However, he does not want to empty his tank and all the fish and change it! Does he have any other choice ? Thanx!