Algae Scrubber Basics

[karimwassef]

So I have 3" x 60" = 180 in2 lit on one side with MH. So 180/12 = 15. The x 0.5 = 7.5 cubes per day capacity?

It's actually a 4" x 72" screen, but the area that receives enough light is 1" short on the width and 6" short on either side.

<a href="http://s1062.photobucket.com/user/karimwassef/media/0E03A93D-1937-49DA-8B77-A0FDD9A9F8E0_zps1elfostg.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/0E03A93D-1937-49DA-8B77-A0FDD9A9F8E0_zps1elfostg.jpg" border="0" alt=" photo 0E03A93D-1937-49DA-8B77-A0FDD9A9F8E0_zps1elfostg.jpg"/></a>

 

[biecacka]

So I can trim mine a bit to 4-5 cubes a day.
Then how many lights or watts?

Corey

 

[Jade5051]

Algae Scrubber Basics

So I can trim mine a bit to 4-5 cubes a day.
Then how many lights or watts?

Corey

I'm making about a 50 sq. in. screen that I'm lighting in one side. I'll power it with 16x3w LEDs which comes out to 49 watts or 1w per sq. in. Using the spreadsheet that was linked just a few post back. Since you'll be lit on both sides the equation will work out to 36-45w of 3w LEDs on each side at a minimum and double that for the maximum.

 

[Floyd R Turbo]

So for a 12x7 screen which is 84 sq inches....how many cubes is that? Then when you say 1 led per the equation 84/8 so that is rounded up to 11. So is that 11 fixtures per side?? Or how many watts/fixtures do you recommend? Is 12x7 maybe too large?? 30 fish in my tank so I need to feed a fair amount. If it's too large, what is a good size for say 4-5 cubes a day?

Corey

12x7=84, /12 = 7 cubes/day

The calc is for the number of 3W Deep Red LEDs per unit area. So 84/8~-11 means 11 individual LEDs per side. That is for the normal light level. You can do as high as 84/4=21 LEDs per side, so somewhere in between, whatever works best geometry wise.

I would also recommend dimming the LEDs, no matter what configuration you use. I have found that using a higher density array (more LEDs) then dimming them and running longer hours works very well.

For 4-5 cubes/day, you can use 4x12=48 or 5x12=60 sq in, or you can use the screen you have and use fewer LEDs, or you can use a lot of LEDs and dim it down, and then you have room to grow, capacity wise. So if you do eventually push 7 cubes/day, you can bump up the intensity, duration, and flow to match the tank bioload.

 

[biecacka]

Floyd, do you have a recommendation on pre made LEDs? I see some on Amazon etc. if I go with more lights but lower intensity, would those work?
Also, let's say I pick a few fixtures and light a part of my screen more than another part. I assume the algae wound grow there, then if/when I need to I could add more lights to use the rest of the screen. Right?
Corey

 

[Floyd R Turbo]

You are correct, you can light just part of the screen, you will get some growth away from the main light area, just not as much. typically.

see the post # in my signature for the LED update, I cover a general guide for off-the-shelf lights. There are so many options, it's hard to recommend just one or two.

 

[biecacka]

Ok thanks.
I'm looking for actual fixtures now.

Corey

 

[SantaMonica]

7.5 cubes per day capacity?

Sounds right. Keeping in mind that 50 pounds of problem rock adds 1 cubes.

So I can trim mine a bit to 4-5 cubes a day.
Then how many lights or watts?

Just use the size you have. Each 12 square inch side would be at least 6 real CFL watts, up to 12. Or 3 LED watts, up to 6.

 

[biecacka]

So 12x7=84. So 42 real watts CFL? Or 36/72 led watts?

Corey

 

[Floyd R Turbo]

For CFL, it's as simple as screen area = total wattage (both fixtures). So 42 actual watts CFL per side = 84W.

For LED, from post 6884:

Figure out what you need per the "unit area" guideline. In the above example, 6x6 screen, minimum level (low intensity), 5x 3W per side. Each is actually drawing 1.5W, so 5x1.5 = 7.5W. Your light fixture should actually consume, at the wall, a minimum of 7.5W. The electronics built into the fixture will draw power also, meaning that you might want to add a little cushion to the number. So a 10W fixture on a 6x6 screen would be about right for a comparable replacement to an array of 5x 3W LEDs.

Now let's add that factor in and parallel it to screen size. A 6x6 screen = 36 sq in. Make it 40. you need a 10W actual-draw LED fixture on each side of this. So you could say that the rule of thumb for a pre-built LED fixture is that you need 0.25W per square inch of screen. That would get you into the Minimum light arena - or "Minimum Intensity", and you need one of these on each side of the screen.

Doubling that would put you on the higher end. 0.5W per square inch - actual wattage draw of fixture.

What you have to watch for is when they use a multi-chip that has 9 1W LEDs on it and they call that 10W. Not necessarily true. But 1W LEDs are actually more efficient than 3W LEDs when you are talking radiant flux output per unit of energy input into the LED, so it's not horrible, just shoot for the higher light level and you'll be OK usually. At best, you will actually be at the minimum level. At worst, you'll be on the low side but still OK.

You'll notice here that the factor is 0.25 x screen size, that is per fixture (each side), which means 0.5 x screen size for total LED fixture wattage. That would mean ~21 LED watts per side. The caveat is the 1W issue. Most fixtures that have individual LEDs with their own reflectors and such might be 3W, but they are much more likely to be 1W chips, or 3W chips that are under driven. Under-driving cheap is a method used by manufacturers to make cheap chips last longer.

Multi-chip fixtures are usually a bit better, they are still 1W chips usually (all grouped together) so they're sort of in between a fixture with multiple 1W chips and a DIY fixture using 3W chips on star PCBs like from Rapid or Steve's. However, they still might call a multi-chip fixture with 18 or 20 chips a 20W fixture, but it may only pull 13W or so from the wall, and that's what matters.

IMO shoot high for wattage on a stock fixture - treat is like a CFL as far as wattage rating goes, so in this case, get 2x 40W fixtures or 4x 20W fixtures. Each 40W fixture will probably pull 25-28W off the wall, and that will get you to the minimum intensity that you want.

 

[Paul B]

I added my water cooled red LED fixture to my algae scrubber. I hope it works because it is blinding. :dance:

 

[Floyd R Turbo]

Nice! My mortar screen is working well, it matured very quickly and the mortar is well over 3/4 gone after a few cleanings. Most of the remaining mortar is in the holes and this has helped keep algae strongly attached in the holes after scraping. It worked perfect!

 

[Jade5051]

I added my water cooled red LED fixture to my algae scrubber. I hope it works because it is blinding. :dance:

Are these LEDs attached directly to pvc?

 

[Floyd R Turbo]

No, that's copper pipe on a stand-alone cooling system (just like his DT LEDs)

 

[Jade5051]

No, that's copper pipe on a stand-alone cooling system (just like his DT LEDs)

Is he using a radiator or just sheer water mass to keep the pipes cool?

 

[FullBoreReefer]

Looks to be a small cooler with fan.

 

[Floyd R Turbo]

Go to his 35 yr old reef tank thread (it's not 45+ yrs old), he shows the whole build. Same with his DT lights. It is a water cooled system with a pump and a remote radiator w/fan

 

[karimwassef]

Wow

 

[_Mackus_]

About how long after starting using an ATS should the algae growth begin?

I read through much of this and the advanced thread, including the post numbers quoted in Turbo's signature. I believe I did everything right. I've got about a 4"x4" roughed-up section of plastic mesh screen (I feed the equivalent of one cube give or take), two of these 10W LED light fixtures that are mounted about an inch or so from the screen on either side, and a 382 GPH Rio pump that I throttled down until it was cascading nicely off the end of the mesh without splashing everywhere (didn't actually measure to see if it's at 140 GPH for a 4" wide slit).

The one step I think I may need to redo and improve is the roughing up of the screen. I read "hole saw" in the guides and must've skipped over the "bi-metal" part. I used a diamond-tipped one that was originally used to drill the holes in my tank, much less jagged than a bi-metal holesaw. I'm wondering if I need to take the screen out and rough it up more using a rasp or something (I don't actually have any bimetal holesaws). It was definitely roughed up quite a bit with the holesaw I used, but probably a bit shy of some of the photos I've seen of how it's supposed to look.

Been running it 18/6 since Sunday afternoon, and don't see any growth yet. I figure that's typical and I won't get anything for a while. Mostly I just want to know when growth usually starts to take place so if I get much past that point without seeing anything, I'll know to try troubleshooting, starting with making the screen rougher. Or to know if I should just scuff it up more right away.

Thanks to all for the advice and for these amazing threads.

 

[AZRippster]

I could see growth within the first week and my wife had to harvest ours within the first month. It also depends on how much organics/food source you have in your water.