New light & Lots of brown stuff ????

Hello All,

It has been a while , I have been very busy with moving and lots of other things. We put a new light on our 29 gallon fish w/live rock only tank but we added to 'hard' corals to the tank, prior to adding the corals (just a few days ago) we put the new light on it it's been on for about a week and it is a...
Coralife AquaLight Pro Metal Halide HQI Clamp-On Pendant - 1 x 150W

Coralife AquaLight Pro Metal Halide HQI Clamp-On Pendant - 1 x 150W <<There is a link to the light.

Since putting this light on we have had a break out of a bunch of brown 'stuff' on the rock and on the sand. Our tank has been set up for a year now and we did move but we kept the same water from the tank and added it back in w/5 gallons of fresh salt the salt is at the right level and all live stock are still living and doing great, just curious what this brown stuff is??? I read somewhere it could be diatoms, but i thought diatoms only came in newly set up tanks??? any help would be great!

 

what kind of bulb are you running? Was it the stock one that came in the fixture?

 

Yes, it is the stock one it's more of clear light, we have looked into getting the kelvin, thinking maybe a 15k would that reduce the brown?

 

Add any new equipment like powerheads, anything at all or new water containers?

 

um, the only thing new that was put in was a heater, but we don't even use the heater because the light itself keeps the water at temperature. Could they have showed up bc of the new heater?..would the kelvin make a difference?

 

Anytime you add equipment with some plastic or glass you may add silicates to the system and cause a brief diatom bloom, while barely noticeable in a larger tank it may seem more concentrated in a small system. If they are diatoms, lighting usually is not a huge factor. I am guessing you already ruled out cyano and dino.