I purchased some Berghia Nudibrachs in May. It seems the last Aiptasia in my tank was gone yesterday. I have a few Berghia Nudibrachs still alive and I like to give them to someone who need them. I caught 6 this morning. Must pick up today or tomorrow in Bay Ridge, Brooklyn.
I had the same whirring sound problem with my Vortech last year. I fixed mine by putting some oil in both bearings after I took it apart. It has been working fine since then. You don't want to take it apart if it is still under warranty.
Google Noisy Vortech Dryside fix for more information.
+1
A hippo and yellow tang should get alone with no problem but every fish is different. I will pick the yellow over the hippo. A hippo will probably get all the food before your fire fish can get to it. A yellow tang will keep you from algae problem assume your water quality is good...
I quarantine using hyposalinity and use display tank water for top off to raise the salinity back to normal after the quarantine period is over. I will also slowly raise the temperature of the quarantine tank to 86 degree if there is any sign of ich on the fish...
Neon Gobies, (yellow strip, blue strip or yellow blue strip), Cardinalfish (Orange Lined Cardinalfish) are nice. I found Yellow Clown Gobies are not too SPS friendly. Some soft corals will overglow a 12g tank quickly.