It is bulbs replacement day on my EZ550reef!
Replacment of the 6x T5 bulbs should have been done long ago.
4x were 9.5 months old
2x were 14 months old
I saw the colors of the corals on the bottom slowly deteriorate for a few months. This process had been going on for more than 3 months. In accordance with the requirement to replace the lamps every 6 months at SPS corals.
It's always a puzzle to get the right flow.
To much blow away the sand
To low means dirt deposition and cyano.
Once in while you need to re-evaluate flow, because of the increase in the coral colony's.
The corals also need flow to move nutrients and waste products.