Fish4cats and eczema

Basically my cat keeps on getting wet eczema - vet treats him for fleas, gives antibiotics and has done blood tests but keeps coming back. I gave him James Wellbeloved as i have had good things about it and eczema. Anyway have any of you lot used fish4cats?
my cat doesn't like fish but he liked the sample of fish4cats so am thinking about switching him to it as it has fish oil which seemed to help his eczema a lot (he had Vitapet before but my sis keeps forgetting to buy it so thought it would be best to recommend something which already has the oil in it)
thanks

I have bought Fish4Cats for mine, and none of them will eat it.