Zoas not opening

[willbaroo200]

Hi all. I have a fluval evo 13.5g I've been running it now for over a year. All has been well until a month ago when zoas wouldn't open. I've had some hair algea which I'm dealing with. I'm doing regular water changes and just introduced some chemi pure into the sump. All my parameters are fine and everything else in the tank is looking good. Any advice would be good. Thanks. Also I'm starting to get bubbles coming up from the sand during the evening.

[Sniperhank]

I see a tank with very low flow. The parameters are starting to creep up and cyano is starting to form. Add a powerhead and see where we go from here.

Also, next time you test give us the parameters. Fine in my tank isn't going to be close to fine in yours.

[willbaroo200]

I do have a powerhead in my tank. There's slot of flow in there.

[willbaroo200]

Top right of screen. If I have anymore flow nothing would open

[willbaroo200]

Nitrate 0
Ammonia 0
Ph is 7.9 which is why I've added chemi pure. Ill send a better picture later of my tank.