Your red algae sounds like cyanobacteria, One of the oldest forms of life on the planet. Everyone gets it and it is not uncommon to see it in newer systems but also pops up in mature systems. The best thing to do is a series of 3 day lights out with actinic lighting only on the fourth day followed by a water change. After that you can resume your normal light cycle. You may need to do this a couple of times spaced a couple weeks apart. Your fish and corals will be fine for the 3 day period and you can feed your tank.
Aside from that you should be focusing on not overfeeding, staying on water changes and siphoning out patches in between water changes and skimming wet. Increased flow should also help and "dead spots" may be the culprit to start with.
Have you tried the baited glass yet for the crab?
Gonipora are beautiful but also can be challenging. Recommend you do so reading on them for best chances of long-term success.
Look forward to seeing the pics of the gonipora.
Aside from that you should be focusing on not overfeeding, staying on water changes and siphoning out patches in between water changes and skimming wet. Increased flow should also help and "dead spots" may be the culprit to start with.
Have you tried the baited glass yet for the crab?
Gonipora are beautiful but also can be challenging. Recommend you do so reading on them for best chances of long-term success.
Look forward to seeing the pics of the gonipora.
. I just had a bit of cyano pop up as well and what helped me was cleaning every part of the sump and overflow. The sump was that bad as far as build up of detritus but the overflow was nasty. After I cleaned those and did a good WC to remove the little cyano I had in the tank, it has not returned. You can turn your lights down/off all you want but if the source is still there to fuel the cyano, it will come back.
