I have some xenia that are growing like crazy. I put some small pieces of rock down for the new ones too spread to. I've moved the new pieces and they pulse alot, but the older originals have't pulsed in 3-4 days. Is this normal? Also I bought some peppermint shrimp on 2 separate occasions, and they were brownish colored, after a week or so they have turned dark red. Is that good or bad. Thanks