Why is this algae taking over coral?

[Gavin1274]

Hello everyone, I have had this tank for a while now and it has been doing great. The corals in the pictures we’re doing great and growing and then one day this algae started growing in spots so I thought maybe the corals bleached there and grew algae so maybe they would fix themselves but after almost a month it is only getting worse and they will sometimes randomly look good in the lives spots but not in other. Please help. Thank you I’m advance

 

[Flippers4pups]

How old is the tank? What's your water parameters?

 

[Gavin1274]

How old is the tank? What's your water parameters?

I’ve had it for a little less than a year now. 65 gallon. Salinity: 1.027. Nitrate: 7. Mag:1460. ALK: 3.0/8.4. Cal: 470

 

[Flippers4pups]

I’ve had it for a little less than a year now. 65 gallon. Salinity: 1.027. Nitrate: 7. Mag:1460. ALK: 3.0/8.4. Cal: 470

It's still possible to get the uglies at this stage. Any idea what your P04 is at?

 

[Adam_C]

Looks like STN or even RTN. When tissue dies on SPS, if it's not able to recover quickly, than algae almost always grows on the bleached skeleton and further stresses out the rest of the colony. You're numbers don't look bad ,salinity is on the high end. Most important is stability. In my experience with SPS the big three - alk/salinity/temp dont like swings and can easily lead to tissue death. Other parameters should be stable as well, but again, just my opinion, the big three are most critical. SPS also do not like changes in general like messing with lights, flow, or swapping out gear constantly. Stable tank turns into mature tank which = happy SPS. Hope this help. Best of luck!