| That's a lot of fish for a 37g tank. Do you think that could be causing stress to your fish? Just something to think about.
I have Seachem garlic. I've only used it a few times and just mixed it with their food. I *think* the only thing known for sure about garlic is that it helps build their immune system. Do a search for that Reefkeeping article from Dec/Jan about Garlic. | 
