Skriz;392616 wrote: Lava rock should be inert; it shouldn't do anything for or against you. BUT, it could have metals that it could leach into your tank.
Do you run carbon at all? If not, it would be a great idea to run some, just in case there are some contaminants in the water column.
I'd also advise some monster water changes; 50% + type wc's. This will bring your water chemistry to an equillibrium.
And to answer your question about "which is worse..": letting a fish acclimate to a tank (at the store) and re-acclimating at home, is better. Why? It'll give time for any parasites to show and the store a chance to treat the fish. It'll also give them the opportunity to "train" the fish to eat prepared foods. Lastly, you can see its personality. Your fish was special though