Here are a few photos of my Opae Ula tank from Feb 2008. Unfortunately, I no longer have this 2.5G tank with breeding population of almost 100. I had to give this up to a friend when I moved from Los Angeles to New York. I followed much of the advice discussed here in the forum, except for the following:
1. I used several pieces of cured live rock to build a structure that provided plenty of dark interior space for the shrimp to hide. This mimics their natural habitat and I believe it was the key to getting them to breed.
2. I did regular water changes, 1/4 gallon every 4 weeks. I very carefully siphoned out water and shrimp poop from the bottom of the tank using air hose and a sturdy straw. Then I quickly poured in a fresh mix of full strength saltwater and fresh spring water, diluted to the proper salinity (which I forget). This mimics the periodic water changes in the anchialine pools in the wild. I think this also contributes to breeding.
3. I ran a small air pump with a stone diffuser full blast twice a day for 20 minutes on a timer. Once during the day when the lights were on, and once at night when they're off, to circulate the water, and simulate the flow of the tides. Contrary to what others say in this forum, my shrimp quickly acclimated to the water movement, swimming in and out of the bubbles, riding the current, not once going popcorn crazy.
4. I fed my shrimp bits of algae wafers and spirulina algae powder. I would break up the algae wafer and toss in 2 pieces, each about the size of a grain of rice, 2 times a week. After 30 minutes, I would suck out the remaining uneaten piece. Twice a week, I would also take a toothpick tip full of spirulina, mix it in a shot glass with ice cold spring water, and then pour the mix into the tank, so that there would be a column of spirulina suspended in the water, from the top to the bottom. In seconds, one shrimp would swim into the blue-green cloud and go crazy, triggering other shrimp to find the spirulina. In the last few months before moving, I stopped feeding altogether because there was so much green algae growing on the sides of the tank.
I plan on setting up a new 15 gallon opae ula tank here in NYC this spring, building upon the success I had with this tank in LA...