For easily accessible foods, I use a varied diet.
Many live plants and Java moss, and Marimo moss balls for fun, but they love picking at them.
Don't over feed, they only need TINY amounts of food!
Petco had Hikari Crab Cuisine, also acceptable for shrimp, today for 3.99 per bag. The OEBT rushed over to the Crab Cuisine much faster than they do to the Shrimp Cuisine.
I have been using the Shrimp Cuisine but it is hard to find locally and very expensive. My shrimp like the Bottom feeder sinking wafers, I list below, the best.
The Hikari Bottom feeder sinking wafer for omnivores, are the favorite, they love this a lot, just give them some pieces of wafers/ package has an orange-ish label. Hikari Algae tab pieces, which they don't seem to love very much.
Also Omega One Shrimp pellets, they have lots of good things in them, BUT do not put much in at a time. I killed a little tank of snails after dropping in just a few, and it caused a big ammonia spike. The fish, snails and shrimp really like it, just be careful!
I also put in a few live brine shrimp when I get them for my other fish and also Hikari freeze dried tubiflex (soaked in tank water for a little bit, yuck, lol and brine shrimp. Would also use blood worms (if dried/soaked), but I am allergic!
Use tiny bits of veggies too but they don't seem especially fond of them. I am growing some organic veggies now for them.
Feed tiny bits so as not to pollute your water.
Also use dried Oak leaves, which I harvest in fall, from unsprayed/treated trees but am thinking of using fresh ones and letting them dry
Also I just bought Catappa leaves (aka Indian Almond leaves/Ketapang) in the hermit crab section at Petsmart (new item). They are little ones so they will fit in the little tanks well!
Also skip feeding every once in a while. It depends on what I feed mine if I skip more frequently.
I would also like to try the Repashy sometime.
I love my shrimp!lol