I am interested in offering my fish an alternative diet. I've read that most fish will eat raw shrimp and clam meat, as well as green vegetables such as peas. However, I experimented with 1 littleneck clam that I chopped into chunks, and some frozen peas that I thawed in the microwave, and the fish didn't seem interested in either. I'm not sure if it is because I served it wrong, or because the particular fish I have simply won't eat these items. I have the following fish:
A siamese algae eater
A Blue Gourami
A pictus Catfish
3 Tiger Barbs
2 emerald Catfish

Should I try different seafoods/vegetables? Should serve it differently? Do they need to get used to this food? Or do the particular fish I have not go for these foods?