LED Lights grew this

[ItchyF1ng3rs]

I have a 10 gallon display and a 40 Gallon sump, which I started in October of 2009. I have about 130 pounds of live rock in the sump and a few rocks in the display. I know this sounds funny but I am going to use this all later in the 300 gallon in-wall aquarium at my new house being built right now.

When I started the aquarium I used 4 - 20watt self ballasted CF by coral life. They worked great but I wanted to experiment with LEDs So on 12-18-09 (about 2 months after starting the tank) I got this LED fixture off Ebay:
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LED quantity: 119pcs x 1 Watt LED (71 White + 48 Blue)
LED configuration: BridgeLux 1w/LED
Color: White and Blue mixed, White: 14000K(14000-20000k),
Blue: 460nm
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This fixture is alot brighter than the CFs and works great (less heat) and it makes the shimmer effect that I like. Also I would like to use them on my new tank but shortly (1-2 weeks) after installing it I got this stuff growing.

It looks like an expanded version of the chaeto grass in my sump.

Here is my current test results:
pH - 8.40
Alk (mE/L) - 2.90
Ammonia (ppm) - < 0.25
Nitrite (ppm) - < 0.10
Nitrate (ppm) - 0.00
S.G - 1.0245

2 ocellaris clowns
1 emerald crab
10 small hermits
15 snails

I use RO/Di for water changes and makeup water. I have a custom build AquaC Nano Urchin skimmer for my sump.

Any idea what this is and how to get rid of it ?

Thanks !

 

[Mitchell0605]

It may be because of excess nutrients in your water. Cut back on feeding and do a few PWC of 10%-20%. Don't try to tear it off or cut it. It might release little spores or something that could grow into more! Good luck.

 

[ItchyF1ng3rs]

Thanks!

 

[dannyb]

Did you cycle the tank? You still have traces of Amm and Nitrite?