Lime green algae in sand bed

[sheeb]

Does anyone know what this is? I’ve never seen anything like this in my tank. It is 100% established and cycled with no new additions besides coral here and there which shouldn’t be a problem. It looks much worse on camera but it’s only in the sand bed not on top. Doesn’t seem to be bothering anything either, all params good, don’t have my sheet next to me but nothing stood out. Only thing I can remember is salinity at 1.026 temp 76. There is also very minimal sunlight getting to my tank. Seems to be that this spot is the worst and the other sides of tank are minimal.

Params: NO3 < 1.0 ppm
PO4 0.2 ppm
Calcium ~400
Magnesium 1250 or so last time I check a week ago
Ammonia 0
Ph 8.1-8.2

 

[EeyoreIsMySpiritAnimal]

Can you scrape/siphon out what's there? What type of cuc do you have? Looks like run of the mill algae to me... Sorry, I know that's not terribly helpful.

 

[a.ocellaris]

Looks like green cyano.

 

[sheeb]

Can you scrape/siphon out what's there? What type of cuc do you have? Looks like run of the mill algae to me... Sorry, I know that's not terribly helpful.

Cuc is very active. Snails, turbos, hermits, pods , and some fish that are even a part of it.

 

[sheeb]

Looks like green cyano.

Never dealt with cyano. What should I do to fix this

 

[i cant think]

Does anyone know what this is? I’ve never seen anything like this in my tank. It is 100% established and cycled with no new additions besides coral here and there which shouldn’t be a problem. It looks much worse on camera but it’s only in the sand bed not on top. Doesn’t seem to be bothering anything either, all params good, don’t have my sheet next to me but nothing stood out. Only thing I can remember is salinity at 1.026 temp 76. There is also very minimal sunlight getting to my tank. Seems to be that this spot is the worst and the other sides of tank are minimal.

Params: NO3 < 1.0 ppm
PO4 0.2 ppm
Calcium ~400
Magnesium 1250 or so last time I check a week ago
Ammonia 0
Ph 8.1-8.2

Looks to me like the regular algae you’d find growing in the sandbed
Here’s my nano tank’s sandbed that’s 1 year and 4 months old.

and now my 2 year old 4’ tank’s sand bed.

 

[damsels are not mean]

Yeah that just happens. It's gonna happen. You didn't do anything wrong. Most old tanks have some sort of algal film in between the sandbed and glass. I had some coralline algae there even.

 

[EeyoreIsMySpiritAnimal]

Never dealt with cyano. What should I do to fix this

I am not sure that it's cyano, but regardless, scrape what you can off the glass and stir up the sand where the algae (basically bury it so it's not getting any light). This will take care of the algae that's currently there.
As I and others have said, it looks to be regular algae... A healthy system will have some and it's not a bad thing.
(Just to answer your question about cyano... it likes low flow areas, so if you do some research and decide that's what it is, increasing flow to that area of the tank would be the first step. Actually, manual removal of any mats of algae is the first and flow is the second )