I'm going to count this this as an absolute, 100% MUST HAVE item. I am seeing visible improvements in all of my corals, in only 2 days. I've never had anything make such an impact.
I've got a prostrata acropora that in 2 days has morphed into a wolly mammoth. A green stag that looks like a green shag. A granulosa that has been brown since the day after I got it, has coloured back up -fast-. A pink birdsnest that has sat stagnant since July has just sprouted branches for the first time. There are also 5 other favourite corals that have just come alive in the past 2 days.
I had 3 powerheads and 2 strong return jets running in the tank, the powerheads all on 5 min on, 5 minute off cycles. It just must not at all have been what the coral needed. All my monti colonies are showing new white tips, and my pokerstars grew 1/8 inch since sunday.
I can't get over the improvement in colour. I have recently been looking at my filtration, skimming and lighting, and it really is looking like poor water movement was holding me back.... I haven't been this blown away with the tank since I first put the DIY LED's on it. Absolutely amazing. It really should be on a list somewhere of 'MUST MUST MUST HAVE's' if you're going to grow SPS.