I should clarify what I said earlier about sources. The two I mentioned were the most apparently viable ones that G**gle searching provided. And as we know, G**gle prioritizes search results in a way that benefits their best sponsors, so it's really not the best or most complete list of sources. I know there are several other good sources for these critters, and some have been mentioned in this thread.
Anyway, my amphipods arrived mid-day yesterday from IPSF, shipped overnight from Hawaii. Because of how I ordered, I received 3 bags of about 20 amphipods each. Actually there were considerably more than 20 in each bag, with sizes ranging from really tiny to fully mature. The shipping cost was not unreasonable, IMO -- I believe it was $29. The pods were packed in double bags in an insulated box. IPSF also included a big ball of red gracilaria and a large mass of green sheet algae (not sure what it really is -- ulva maybe?) -- this bag of algae is what IPSF calls their 'Pod Mat'. Pod survival seemed very good, and there was a lot of activity in the bags. I spent about 90 minutes getting them temperature acclimated to their new home (a 5 gallon aquarium with heater and airstone and a few fist-sized pieces of porous, dry reef rock).
I may have made a mistake here, because I didn't test water or acclimate the pods for salinity. I had filled the breeding tank with new saltwater at the same salinity I keep my other tanks (34ppt). IPSF, as I recall (maybe incorrectly), said they kept their breeding tanks at 30ppt. I was thinking that was not a big difference and it was getting really late in the evening, so against my best judgement and not following my usual procedure, I just released the pods into the breeding tank without doing additional acclimation. Some of the largest pods may not have survived this, and this morning I have several large dead amphipods on the tank bottom. The smaller pods and several of the really large ones survived just fine, however, and are busy and active this morning.
So that's where I am today. My plan is not to go whole hog into breeding amphipods -- I just want to let them reach a population where I can re-seed my display tanks with them for a while, to re-establish their presence. My plan is to occasionally remove one of the rocks from the breeding tank and either place it in the refugium section of the sump or shake it out in the refugium to release them into the water there. I need to refresh my memory on their life cycle though.
Sorry for the length of this post. It's not my wish to hijack the thread... but hopefully there is some useful info here for somebody.