Ive used both spirulina and yeast to grow daphnia and moina ( both are raised the same and i will only use the name "moina" for ease of writing)over the years, both can have a very bad impact on water quality if over used, i have also read that yeast fed moina can be bad for larval phibs, i personally have had no noticible probs but i would defer to the guys who have said it. I grow moina in 5ft tanks outside, heavily planted lots of detritus on the bottom, i "feed" the tank with pellets, fish flake, waste bloodworm from axolotl tanks. These food items rot cause bacterial blooms which feed the moina and other bugs such as hog lice, blackworm, mozzy larvae, snails and various nymphs. Plants covered in empty axolotl egg cases are also dropped in there where the bugs clean them up for reuse, this particular food source causes a boom in hog lice and moina, they love it. Water volume makes life easy when breeding moina, small tubs are easy to over feed and pollute, killing the moina.
After you have your colony established and feeding regime sorted your next step will be to prevent the boom bust cycle that moina go through. You will literally have millions of the little guys, they exhaust the food supply and crash down to a residual population, it takes them quite a while to bounce back to the original numbers. What you need to do is heavily harvest when the population is dense, this is a deliberate crash which the population bounces back from a lot faster than a crash caused by food shortage. This is due to the two breeding methods used, live bearing and eggs production. When times are good they are live bearers, when environmental conditions arnt optimal, such as a reduction in available food they develop eggs which hatch when conditions improve, this means a population which changes breeding from live bearing to egg production takes longer to recover than a population of live bearers which is deliberately crashed.
This link gives further info about breeding moina
This document provides an extensive overview of the biology, culture methods, and practical applications of Daphnia, specifically focusing on the genera Daphnia and Moina. Daphnia, known as "water fleas" due to their size and distinctive movement, play a crucial role in freshwater ecosystems and...
edis.ifas.ufl.edu
Relevant bit if you cant be bothered reading the whole thing lol
"Under adverse environmental conditions, males are produced and sexual reproduction occurs, resulting in resting eggs (ephippia), similar to brine shrimp eggs. The stimuli for the switch from asexual to sexual reproduction in populations of
Moina is an abrupt reduction in the food supply, resulting in an increase in resting egg production. However, it is advantageous to keep the population well fed and in the asexual mode of reproduction, since fewer progeny are produced with resting eggs."
