Green hair algae, and cyano are taking over my tank. And ticking my corals off. They are eveywhere. Any advice without fosing chemicals? My nutrients are 0.04 phosphate, and 6.8 nitrate been dosing neophos and neo nitro.
In your current situation, the growth rate of the algae is high enough that you had to start dosing nutrients to prevent your system from bottoming out. However, by doing so your'e also maintaining the perfect conditions for it to flourish, as well as cause bacterial instability that leads to Cyano Bactria take over.
My suggestion for you is simple - clean it up, manually and persistently and make sure you have enough flow.
- Siphon the cyano as it appears, daily if possible.
- Pull out any algae you can with your hands
- Scrub algae leftovers with a toothbrush
- Carefully clean your sand, not all at once to not disturb it too much.
- Add CUC - Lots of Snails, Urchins, sand sifting gobbies, shrimp, etc
- If your tank is big enough, add tangs - they are great algae grazers
- Filtration - When you remove cyano and scrub off algae you want it to be exported out of the system, use socks, filter rollers and water changes to help you with this.
- Make sure you have enough flow, cyano wouldn't be able to take ahold in places with enough flow.
Once you see you PO4 and NO3 starting to climb up, you should decrease and eventually stop dosing them.