Lights

[Brian Fuehrer]

I have a scrubber that is a little over two weeks old using a 7 by 7 screen. I have a brown spot the size of a baseball on my screen due to the light concentration. I'm using one 23 watt CFL 2700K on each side of the screen about 5 inches away from the screen. I'm currently running 18 hours on and 6 off. Should I decrease my photo period or move the lights 6 inches from the screen? Any help would be greatly appreciated!

[SantaMonica]

Best is to increase flow. Next you can add iron. Next best is move the light 2" farther away. Last best is reduce light to 12 hours.

[Brent1128]

If its a dark brown I think you want to run lights longer. Maybe 20-21 hrs until you get greener. If light brown then yeah move light back or reduce light.

Are you using a reflector of any sort? A cheap clamp light from menards will help. I also found a CFL floodlight that is 23w, but unlike others that say is 75w equivalent, this one was 100w equivalent. Still 2700k.

I have just ordered two LED bars to upgrade two of my four CFL lights. You'll find the link on this site. Havent seen any actual results other than the youtube video posted on the for sale site. Looks solid. A few from this site just bought some but they havent posted any reviews. I'll update the thread once I can compare the two LED bars on one side vs. 2 23w CFLs on the other side. Screen is about 9 x 10.

[kerry]

Both of you guys are running screens a little big for your light. Its likely that a smaller screen would produce much better nutrient removal. Try to get closer to 6x6 at the most with the 23W CFL, I was using the 44W CFL with a 5x6 screen a had good results.

[Brent1128]

Hes running one CFL per side while I'm running two per side. 90sq inches of screen means I need at least 90 watts. I'm at 46w per side for a total of 92 watts.

[Brian Fuehrer]

If its a dark brown I think you want to run lights longer. Maybe 20-21 hrs until you get greener. If light brown then yeah move light back or reduce light.

Are you using a reflector of any sort? A cheap clamp light from menards will help. I also found a CFL floodlight that is 23w, but unlike others that say is 75w equivalent, this one was 100w equivalent. Still 2700k.

I have just ordered two LED bars to upgrade two of my four CFL lights. You'll find the link on this site. Havent seen any actual results other than the youtube video posted on the for sale site. Looks solid. A few from this site just bought some but they havent posted any reviews. I'll update the thread once I can compare the two LED bars on one side vs. 2 23w CFLs on the other side. Screen is about 9 x 10.
Thanks for your input! I look forward to seeing all the info you have on your LEDs. Please let me know your results. Thanks again.

[Brian Fuehrer]

Thanks for your input! I look forward to seeing all the info you have on your LEDs. Please let me know your results. Thanks again.

By the way, I am using 8 inch round reflectors. One on each side of the screen.

[Brian Fuehrer]

Best is to increase flow. Next you can add iron. Next best is move the light 2" farther away. Last best is reduce light to 12 hours.

Thanks for the info SM! My flow is 300 GPH right now and based on the calculator you provided I think it should be a minimum 240GPH. I'm going to give the iron dosing a try and see what happens. I don't know if this matters but my screen is technically 12 inches long for the purpose of reaching the water in the sump.

[Brian Fuehrer]

Both of you guys are running screens a little big for your light. Its likely that a smaller screen would produce much better nutrient removal. Try to get closer to 6x6 at the most with the 23W CFL, I was using the 44W CFL with a 5x6 screen a had good results.

Thanks for the input kerry. I think the way I worded the question was a little goofy. I have single light on each side of the screen.

[rleahaines]

Thanks for the info SM! My flow is 300 GPH right now and based on the calculator you provided I think it should be a minimum 240GPH. I'm going to give the iron dosing a try and see what happens. I don't know if this matters but my screen is technically 12 inches long for the purpose of reaching the water in the sump.

A longer screen to reach the water in the sump should not matter very much if you concentrate the light on the effective area. I currently have a longer screen with lights concentrated near the top half. I get algae growth spread out a bit, that's all.

The point here is that you are not just growing algae, but using the algae growth to use up nitrates and phosphates. Even a thin growth of algae can do this.

If you have enough light and good flow, it should work.

[Brent1128]

Are you using the spiral CFLs? Or are you using the CFL floodlight? You want CFL floodlight.

[Brian Fuehrer]

Are you using the spiral CFLs? Or are you using the CFL floodlight? You want CFL floodlight. Your using floods? Everywhere I've looked recommends the spiral which I'm currently using.

[SantaMonica]

Floods are good for small screens, and spirals/reflectors for large screen.

[Brian Fuehrer]

Is a 7 inch by 7 inch screen considered small? If it is and I go to the flood lights should I still use my 8 inch reflectors for the flood lights? Thanks for your help SM
Floods are good for small screens, and spirals/reflectors for large screen.

[SantaMonica]

8 inch reflector is probably best, because a floodlight would need to be place pretty far away from the screen.

[kerry]

7x7 would be what I would consider larger. Like SM says stick with your 8" reflectors.

[Brian Fuehrer]

8 inch reflector is probably best, because a floodlight would need to be place pretty far away from the screen.

Thanks SM Ill stick with what I got right now. I wouldn't have the room to keep the floods far enough away from the screen anyway. When I can get around to it, would it be okay to post a few picks of my display for you to look at? I have this brown hair algae problem on my live rock all of a sudden. I don't know if it is a scrubber problem or maybe something to do with my new LED lights I put in a couple of weeks ago. The algae was being removed from the back and side walls of the tank but now it seems to be coming back. I have been dosing iron like you suggested a few weeks ago on another thread I had started. I think it was waterflow through the slot if I remember correctly. Thanks again!

[Brian Fuehrer]

7x7 would be what I would consider larger. Like SM says stick with your 8" reflectors.

Thanks for the input Kerry! It is much appreciated.

[SantaMonica]

Yes do post display pics, but any algae in the display is by definition a scrubber problem.

[Brian Fuehrer]

Hey SM, I'm finally getting around to posting those pics. I just got back from Hawaii, and the brown hair algae is alot worse then when I left. I cleaned the screen when I got back and I also changed the light bulbs. Hope you can steer me in the right direction of getting this problem solved. This scrubber worked for the 1st month and a half great but now the last three weeks have been a strugle. I'm going to do my best to upload some pics for you. I hope it works because I've never done it here before. Thanks again!5336]

[SantaMonica]

Well those bulbs seem very small. Move them closer until you either get green or a bald spot.

[Brian Fuehrer]

Thanks SM. Just curious what you mean by the bulbs look small. They are 23 watt CFL's 2700k inside 8 inch round reflectors if that helps. I'm about 5.5 inches away from the screen right now. Should I move it say 4 inches away from the screen? Thanks!

[SantaMonica]

Just seem small in the pic. Yes move closer until green or bald spot.