Am I Crazy or Somethin'?

My water has always tested out great.
0, but sometimes 10 nitrate
0 PO4
0 Ammonia
0 nitrite
8.2 pH
8-9 dKH
1.025 S.G.
420 Ca
But for the past 3 weeks or so, I've had major algae issues. Thought to be a contributing factor to my LPS corals not looking too happy and some dying.
Here's the proof. I need to know if I'm going mad or is everyone else seeing acceptable levels?

0 PO4


0 NO3


BUT...
Algae on the sand


GHA on the Rocks


More GHA


And Bubble algae on some rocks


In a few short weeks, My tank went from one of the best I've personally seen in Trinidad to a reef situated just by the exit stream of a sewer!:-X

Any Ideas on what else could be causing this mess?
I went by a friend to test RO/DI TDS which read 0.14 so I changed my carbon in the unit. I have to find some place that sells the Sediment filter in Trinidad. I bout the horizontal unit instead of the vertical one and cant find filters for them anywhere. Didn't get a chance to test TDS again as yet.

 

The only thing I can think is that the algae is consuming the nitrates, so that's why they aren't showing up when you test. And bubble algae can grow in perfect water, so that doesn't have anything to do with parameters.

Algae sucks!!!

 

Could this algae outbreak have started because I vacuumed the sand bed a couple times?

 

Agreed ^^ Most likely the GHA is storing all the nitrates and phos. therefore they are not showing up on your test kits. I would start with manuel removal and get as much of it as you can. Make sure your RODI is reading 0 TDS before mixing water.

Do you have a refugium?

 

How deep is ur sandbed? If it 3" or greater that could be the culprit.

 

Depending how deep your sand bed is. When you vacuumed you may have unleashed a lot of nutrients.

 

:-/Hummmmmmmm it's between 2 and 3 inches. Some parts higher than the other.
No refugium but I have an algae scrubber.

If indeed the vacuuming of the sand bed is the culprit, what's the best way to remove the algae? I usually do manual removal of some areas daily.

 

The TDS at .14 would definitely contribute to the GHA and the algae would be consuming your nitrates and phosphates giving you false readings. Also, how old are your lights? If your lights are close to the year old mark, they may have shifted lighting spectrum and are encouraging the algae growth.

 

I have to get a new sediment filter and test the RO again.
I'm unsure of the exact age of the bulbs. Cant remember when I put the new fixture up. I'll do some back tracking. But they're no more than 7 months old.

 

Blumoon has an excellent point about your bulbs!

IME GHA should just be able to br yanked out with your hand. It almost peels of in mats, or you could use a net along the top of the sandbed.