Algae outbreak!!!

[PapaReefer]

Hello

Our tank was established and cycled in January. After setback with first clownfish dying from Brooklinella we went fallow for a while.
Tank was crystal clear and everything looked great.

Last Sunday we picked up some coral frags - hammer, torch, mushroom, GSP and clover polyp.
They were doing great, opened up and even looked like they grew a bit That lasted 3 days and then things deteriorated very fast.
Thursday morning I found tank covered in brown stuff - sand, glass, rocks. but corals seemed to be still doing ok. I syphoned as much as I could that brown from sand, did water change.

Today corals look much less happy, clover polyp does not even open and I found stringy brown stuff on it...

We do use RO/DI water by the way and did not run lights on full blast to let corals acclimate.

Some videos to show what is happening:



So.... what is it? what do we do? Are corals in danger?

 

[Idoc]

Well, the tank is about 4 months old...this is a prime time for a diatom bloom to be occurring. But, I always push that reefers need to invest $80 in a good microscope in order to look closer at stuff. Guessing makes it difficult to come up with a game plan of attack.

One of the plug pictures above looks like green hair algae...but, I cant get the video clips to load right now on my system. I think I'm having a connection issue right now!

Please test your nutrients as well and post the results...especially nitrates and phosphates. It wouldn't hurt to go ahead and list your salinity, ph, calcium, alkalinity as well. Hopefully you don't have a nutrient depleted system and introduced dinos on those frag plugs. I'd be really surprised if a dino bloom exploded in only a few days though.

 

[PapaReefer]

Reporting back with test results:

• Ph = 8.2
• NO2 = 0.05
• Ammonia = 0
• Mg = 1000ppm
• Alkalinity = 8.4
• Ca = 450ppm
• Po = 0
• NO3 = 0.25
• Salinity = 35

We also picked up Mexican Turbo snail and a couple of Nassarius snails.
Turbo is one heck of eating machine - he cleaned up most of the rockwork in one day. Now he is working on glass. He also eat hair algae from Polyp frag and coral looks very happy now. Downside - lots of poop from this guy

Not sure if I see any effect from Nassaius snails as sand is all covered in brown algae with just a little clean spots here and there. Probably it will take them longer