I keep cleaner wrasses ONLY from Sri Lanka. I have no trouble with the cleaners from this source eating and surviving, and by the time I sell them to other hobbyists, they are eating multiple foods, like frozen brine, mysis, blood worms and also, spirulina flake food.
If I have trouble getting one to eat initially, I feed them ground up beef heart mush, ground appropriately sized for the size of the specific cleaner. Some small cleaners need a very small particle size at first.
Now for my biggest pet peeve, brine shrimp nutrition.
First though, let me say that I believe that one should feed many different foods to the tank, not just one or two, and one of them is brine shrimp, frozen and live.
The biggest misconception of brine shrimp nutrition comes from the different ways label information is presented. Most frozen brine shrimp list protein levels on the packaging, based on total WET WEIGHT content of the package which includes the packing fluids as well as the shrimp fluid as well.
Other frozen foods tend I think for the most part, to list their % levels based on DRY WEIGHT percentages.
With respect to live brine shrimp, the biggest problem is the retailer who many times does not feed the shrimp, or feeds little or inappropriate foods for them. By not feeding them, water changes are kept to a minimum because there are no fecal pellets being produced to decay and foul the water.
If you buy any, at least feed them something appropriate before feeding them to the fish. Spirulina is my favorite, especially the almost pure stuff.
Brine shrimp do indeed have decent levels of protein.
Many foods like spirulina flake food have protein levels around 45% dry weight percentages, but brine shrimp juveniles or adults have protein levels 50% to 62% for aquacultured brine, and 50% to 69% for wild caught brine shrimp, again given in dry weight percentages. These figures are for brine shrimp BEFORE being gut loaded, which can increase protein levels or fatty acid or diliver vitamins or medication to your fish.
This information comes from probably the best authority on brine shrimp in the world, the ARTEMIA REFERENCE CENTRE at the University of Ghent, who produce most of the factual information for the marine aquaculture industry that uses live brine shrimp as a part of the feeding regime to produce food like fish and shrimp for our tables.
Please check out the link below from the United Nations site, and for NUTRITION info, scroll down to section 4.4.1
CLICK HERE AND SCROLL DOWN TO SECTION 4.0 ARTEMIA