LED Green Coraline

background on system 65G tall(24in) 20L sump 9.5 return lighting 38 cree Leds 20 RB 18 CW 60 degree lens about 8 inches above the tank. tanks been running about 6-7 months. mag 1380ish calcium 440 dkh 10. no detectable phos ammonia. now for the question. the fixture is dimable but i run everything at about 90%

anyone seen any correlation between the intesnsity of light and green coraline algae? i have small patchs of pink/purple but it would seen that my rocks are covered in what i believe is green coraline. it doesn't look "fussy" or "stringy" like nuisance algae. I tested the focus of light while building the tank at 8 inches above almost no light touches the glass(6-7 months cleaned glass about 3 times) the tank has no "LIVE" rock all DIY base rock coraline was introduce via buld up on power heads used from older tank. second question would anyone recomend moving the fixture up? sorry for the long post any input would be appreciated.

 

You will need to introduce the purple coralline algae if that is what you are wanting. If you have and you are saying that purple coralline is just not growing, it just could be that type does not do well under strong lighting. Different types "behave" and grow differently under different intensities of light.

 

As mentioned above I would find a nice small piece of coraline covered live rock. Adding this will help with bio-diversity as well. Coraline comes in many different colors, so I very much believe that it could be green even though I have not witnessed it. I have some red, pink and purple. Also, 90 percent on CREES is quite a lot of light and pink/purple coraline tend to like less light imo

 

yes all the pink/purple does seem to only grow on the bottom 25% of the tank.. thank you for your inputs. funny part is my sump that is powered by a screw in power compact has more purple/pink coraline then my DT tank..

 

your sump is kickin because the light is not so bright down there. ;D

 

By 6-7 Months my rock was fully covered with about 50% green 50% pink coraline with PC lighting. By the 1 year mark it was all pink. Upgraded to a pair of Boostled MU 125's, and over night it all turned purple. I would just wait it out I bet it slowly changes, or you could get a good purple rock and attempt to seed with that (however, thats what I did in the begining due to having all dry rock, and I still had a year with some green). I personally like the variation, and hope that the additional dry rock that I just added has a little green to it.

 

I moved my fixture another inch up. and reduced the output a bit. time to give it a few weeks. and hope for results