Where did you buy the pods? I am looking to get some to help start with the sand
You should have an abundant starter stock of amphipods and copepods in your liverock. If this is a new tank, give them time to reproduce. Liverock is an excellent source for a diverse population of microfauna. Every worm, bug, pod in my tank has come from liverock or sand from established tanks.
Your description says 150lbs baserock. Is that to say there is no LR
in your 75? If so, I would exchange the LR
in your 30 for baserock from your 75 so it can seed your sand for free. Although copepods are microfauna, they don't live IN the sand. They live on it. For sand you want worms. 3 or 4 varieties usually. Again mine all came from the LR
. Try to trade for sand out of other tanks. Much cheaper and arguably more effective than purchasing detrivore kits ($$$).