My scrubbed tank (pics)

Here are some pictures of my scrubbed tank. It is not a perfect tank but It has been up and running with a scrubber as the only filtration for at least 5 years now. I have messed around with water changes,skimmers,and other filtration over the last few months none of them I was thrilled about. I do have some very minor issues that I would like to discuss here. Have a look and feel free to say anything!Attachment 4700Attachment 4711Attachment 4710Attachment 4709Attachment 4708Attachment 4707Attachment 4706Attachment 4705Attachment 4704Attachment 4703Attachment 4702Attachment 4701Attachment 4712

as you can see I am getting some algae in the display and in the sump. I find this strange because in the 5 ish years I have been running the scrubber there was zero algae. Also there is that patch of yellowish rubbery stuff on my screen. That stuff showed up about a year ago and I have tried everything to get rid of it including screen cleaning,new LED lamps,more flow,iron,not cleaning,and more. There is also bubble algae and some kind of macro that grows on my power heads. Maybe I am just feeding to much? I do feed about 3-4 cubes per day.....

Well it's pretty clear that the uneven light is causing a loss of filtering power. One part of the screen is under lit, another is burned.

If you can't pull the lights back, I'd add a second scrubber.

But the lights are centered on the screen? And there is slightly more flow an the burnt looking side? I am not being argumentative and will take your advise but just want to make sure you have all the information I can give ya

But the lenses are focused in one spot. Which is burning.

Ok well I rotated the lamps about 15 degrees to the green side and moved them back about an inch. I also set the timer to 15 hours from 16.5

Do you have all the lenses installed on those PAR lamps? Not sure if this was discussed in one of your other threads, but I know I've discussed it in many other similar threads (regarding PAR lamps)

I do agree that you are severely burning the screen right where the lamps are pointing. This is a sign of photo-saturation, likely due to the blue LEDs. You're going to have to find that "happy spot" where the lamp is not too far away to lose intensity, but not too close to burn. Knocking down the intensity of the blue LEDs is the main goal first, either by removing lenses, adding a little piece of diffuser over each of them, or partially covering them with masking tape. That alone may solve your bald spot issue.

ok Im not sure how the screen is burning only on one side, but I guess it is :(

So now what option is the best option? 1. Move lights a greater distance away and leave the optics in place.
2. Remove all the blue optics.
3. place some semi transparent tape over blue optics.

I am well aware of the fact that PAR is not the same as LUX but is there a way to use my lux meter just to see why maybe the screen is burning so bad? The LED's that make up this par bulb are only about 1.5 watts each so I am having a hard time grasping how they could burn my screen so easy. I have seen people running phillips and cree 3 watt led's at full power and not have burns like this??

Just as a side note: Back when I was running CFL lamps on my scrubber I never had burn spots but I also was never able to grow thick green hair algae, back then my growth was always thin and slimy but it did seem to filter well. Now with the LED lamps I get very thick green growth with large burn spots.

forgot, I also wanted to ask about the main tank lighting. Over my display I am running 12 cree royal blue,2 cree royal purple(almost UV) for 12 hours per day and 12 cree cool whites for 9 hours per day,all at full power.They have mostly 80 degree optics and sit 7" above the water line ,,they are about 27" off the sand bed. Could this make it hard for my scrubber to out compete the display algae? If so I could rais the fixture up and cut the hours a bit.

It has to do with proximity and intensity. I run 3W Philips LEDs but they are 2" on center, fully perpendicular to the screen, 2" away from the screen, and the blues are at half current. Your lamps have all the LEDs crammed right on top of each other and since the intentisy peaks right in front of the LED and then goes down like a bell curve radially, when you put 12 of them in a tight pattern then put optics on them your intensity goes through the roof and overpowers the algae.

You say you are only getting the burning on one side, but pic 008 and 009 (5 and 6 in the original post) are opposite sides, are they not?

What I personally would recommend is removing the bezel and then removing all the blue optics as step 1, as well as any optics that are over red LEDs in the center - leave the optics on the reds around the perimeter. Don't change anything else. Give it a week or two and see if growth fills in.

I don't think you will need to change anything else, but if it still doesn't start to fill in, then I would place a small piece of prismatic diffuser material over the blue LEDs.

It might help to see a picture of the lamp while it is on so I can see which LEDs are red and which are blue. The arrangement can affect things, and different lamps have different arrangements. You can provide a link if you want

Bud