A few things here to note. First, bloodworms should not be fed more than once a week, and as a treat; they are not that nutritious, and they do cause some issue, fat I think. Frozen (fresh frozen) are preferable to freeze-dried, but only once a week whichever. If the freeze-dried, soak them thoroughly in tank water before feeding them, as freeze-dried foods eaten immediately will swell up inside the fish and cause problems. Flake food does not do this, nor does pellet, or so I am told. I never feed freeze-dried any longer as I cannot be bothered with the fuss.
A variety of foods may not be necessary if one uses the high quality foods but it cannot hurt, and most will agree the variety is better for the fish. Not all fish foods are as nutritious or healthy as others, due to additives, fillers, preservatives, and fish do often seem to have preferences. I use Omega One because they do not have any of these nasty things. New Life Spectrum is another good brand and I use their basic flake. There is another, or two, that I cannot remember the names and I don't use them anyway. I also feed Nutrafin's tablets once a week (they do have some of that meal filler) as they contain chopped earthworm and the cories and loaches really go for these. Also Nutrafin's Bug Bites which allegedly is whole tiny bugs, though there is some filler in these. But only once a week, so the dried foods fed four times a week are frankly the best you can get.
On the vegetarian fish/foods, yes, you should be using a food like the Omega One Veggie Flakes (or Veggie Rounds for substrate fish). These foods have all the needed nutrient vitamins/minerals/etc and no whole vegetable or I suspect combination of veggies can provide this. Basic foods fed most often should be prepared foods for this reason, unless you are able to provide complete nutrition with natural live foods that are required by the species of fish. Think of vegetable matter (blanched spinach, squashes, etc) as "treats" but never staples.
The late Jack Wattley probably knew more about discus than anyone, and he frequently wrote in his monthly TFH column that the best foods for discus were prepared foods because the good brands are as wholesome and nutritious as you can get, and as good as any preparation you could come up with. He raised hundreds of award-winning discus for many years.
Buy smaller cans of prepared foods because once opened they obviously can deteriorate and lose some of the nutritive value over time. I now freeze these foods; I open the new container and take out a bit into my older container, maybe enough for a couple months, and stick the new container in the freezer. Then when I use up what I took out, I take out some more. I learned that on this forum, from AbbeysDad I think, but whomever it was, it is good advice. I often buy the large size as you save a lot can to can over the smaller, and freezing preserves the dried foods.
I've been watching them closely while they're eating - if I give them the "recommended" portion I end up scooping out leftovers with a net later. The molly only seems to want a bite or two of shrimp pellet, since he spends all day cleaning algae off leaves and roots. Maybe the fish and I can do a weekly fasting day together, ha.
Veggie flakes it is. I like for all my animals to have the best diets I can give them; it really pays off in the long run with cats, dogs and birds, so I'm sure fish are no different. Thanks for helping me figure out what to get. I was so focused on emergency cycling for a couple weeks there that I hadn't got around to researching food.
