New light and algae issues

[The sea slug]

Hey, all--
I just got a new light, and it's one of those whose color balance I can adjust manually. I can't seem to figure out how to adjust it without algae exploding all over my tank; I've tried reducing each of the different colors (pink, cyan, blue, purple, and cold white), I've tried just reducing the number of hours it shines, and I've tried cutting back the moonlighting. What am I missing? There's algae everywhere... here are the light specs:
168 LEDs
1350 lumens
25000 K (color temp)
47 PAR at 18", 375 at 3"

My tank is 37 gallons and 18" deep.

Thanks guys!

[mcgyvr]

Why do you think the algae is only caused by the light? Thats not that strong of a light anyways..
What are your nitrate and phosphate readings?
Are you using ro/di water?
How old is the tank?
How often are you doing water changes?
Got a full tank shot showing this algae problem

[The sea slug]

The light is the only thing I've changed recently, and its introduction matches the start of this algae bloom, so it seems to make sense... I do water changes every two or three weeks, nitrates and nitrites are at 0, phosphates are less than .2ppm (though I've heard that sometimes low readings are a result of algae just absorbing it all--it doesn't mean it's not there. I do run GFO to try and keep phosphates down). It's a five-year-old tank, I use ro/di water. My pH is a little low, but I'm trying to get that up with crushed coral. I just used a reef-safe red slime remover to see if I could knock out some of the stuff coating the sand and the walls, but it only worked for a day or so, and it's not safe to repeat the treatment yet.

I really don't know what's up with this.

[mcgyvr]

A change in light intensity and or spectrum can certainly cause changes in the tank..

Red slime remover products are typically something like an Erythromycin product in that it treats/kills bacteria.. Its certainly possible that its usage also played a part in an increased algae problem..
Do you still have the cyano problem?
Is this cyano what you are calling an algae problem? Cyano is a bacteria not an algae?
Cyano is fueled by light too..

A picture would be required here to continue to diagnose/help..

[The sea slug]

Yeah, I know it's not algae. I suppose I sort of lumped all of my photosynthetic problem species into one category when I asked the question. Anyway, what I've found is that sometimes the red slime remover makes it easier to detach the algae, which, along with the (brief) cyano removal, was helpful... Here, I'll attach some pictures of the mess. You can see a lot of cyano on the walls, and plenty of algae growing all over one of my snails.

[SantaMonica]

Let it settle in, and don't use too much gfo.

[mrg02d]

I’d look for other sources fueling the algea. Don’t trust your test kits while algea is raging since they are absorbing nitrates and phosphate like you suspect. When is the last time you checked your RODI tds?

[reeftivo]

looks like a bacterial bloom to me.

do you carbon dose?

if so, cut the dosage in half.

a UV sterilizer works wonders on bacterial blooms.

I'd also turn the white channel, green channel and cyan channel down.
you should be able to run the blues much higher.