I can't necessarily post a protocol here, but there are a few things I think are important that are worth mentioning that hopefully can help you and perhaps other breeders as well.
Matt, your idea of revisiting everything is good I think--it's something we do often when we are looking to improve.
In this case, I would start from the beginning--Broodstock nutrition and care. This of course has to be optimized in-order to have the best quality larvae to start rearing quality fish. A couple of feedings per day is probably enough. Pigment-rich foods are important, as is getting enough quality protein. One "easy" food that I like to use in addition to other feeds, to make sure fish get enough protein, is chopped seafoods (table shrimp, mussels, squid, etc). This seems to help if there is any problem with the eggs going to-term and certainly will increase number of eggs and larval health -- "strong larvae," I call them. Other breeders have cautioned against feeding too much shrimp (due to egg-binding) or squid (due to fatty liver problems), so perhaps feed with caution and don't overdo it (whatever that means?!), but I've only a couple of times seen egg-binding, and it was always with new spawners that subsequently recovered and spawned normally. This is from feeding lots of shrimp/squid to hundreds of pairs for more than 10 years now...feeling old
For the larval care, I think Chad has it right-on, but how to get there? ("good food and water" was the gist of his response I think). An airstone or two within the rearing vessel is pretty standard for most breeders, but I find that most use too little air. The larval fish (even smaller clown larvae like maroons and perhaps especially maroons
) can handle and seem to appreciate good flow in the larval tank. Keeping this air going and the tank circulating throughout larval rearing does seem to help. IME, maroons seem to occur in very shallow water -- whether or not this has anything to do with their larvae preferring/tolerating a lot of flow in the larval tank I couldn't say, but it's just a thought I had...
One thing to do for water quality on a larval tank/tub where you are doing something special and want the best fish is to put it on a "drip" from a larger reservoir of clean, newly-mixed (aerated, heated) saltwater. This way you can flush the rearing vessel with clean water. This almost can't be overdone as long as you are able to keep food densities high. Speaking-of, this also helps, because flushing out the old food allows you to add fresh live feeds (rotifers/brine/copepods, whatever you are using) which will have more optimal nutrition than food that has been swimming around in a clean larval tank for hours/days.
When they begin to take prepared foods (the importance of quality here is obviously important), make sure that you can either keep that "flush" going or put them onto a central filtration system to keep the water clean. As the fish grow, large waterchanges on the system (and siphoning the tank bottom) will keep the water quality high so that they will continue feeding strongly. High water quality throughout larval rearing also does seem to reduce deformities.
Another note--I know that some breeders have suggested a 24-hour light cycle, but I prefer something closer to 12/12. This isn't to say that it can't work, just my $.02. I believe that the rest period is important (for fish and people, since you don't want to have to feed in the middle of the night!). The larvae will feed actively all throughout the "day" period though, so food should be available during that time starting with lights-on.
Using these "philosophies," we don't get enough misbar ocellaris to make them available, perhaps 1/250 orange ocellaris show misbarring. The same thing is now happening with blacks as we narrow-in on the things I've mentioned above. Hopefully this can help? I'll post a picture to prove it if I can figure it out...
