Algae Scrubber Basics

Ok I need to back up a bit, the suggestion I made regarding removal of optics was mainly regarding the PAR lamps that many have used for waterfall scrubbers. Justin, I can't recall if I specifically told you to remove your optics, but when you take into account that you are running a horizontal (which needs more light) and you have a limit to the proximity to which you can lower the light, I think in your case you might want to use the optics. If I told you specifically to take them off that was premature. Now with your results and knowing your distance limitation, I probably would not have recommended removing them. I only recall mentioning that I thought the AIs did not have the optimal spectrum.
 
No, sorry if I inferred you told me to, I was working on the suggestion of Salty Joe, I'll put them back on today. They come with the 40 and 70 degree optics, any thought on moving them around or putting them back to stock, I think the center are four 40 and the outward 4 are 70.
 
So It's a little hard to get pictures of my current scrubber setup, but It's working wonderfully. I built it using the overflow and air from venturi. Here's a couple super simple sketchup models I made before building it:

This is the front view that one would see if opening the cabinet doors. There are four total chambers (the first and second are split by a baffle that runs parallel to the front pane) The water enters the rear left chamber from the overflow, runs through the scrubber, over the baffle into the front left chamber (currently tumbling moving bed media), down under the first perpendicular baffle into the large return chamber (also a refugium). The last chamber is separated by a large glass baffle which rises to the top of the sump and holds ro/di water for my auto top-off.


Here is the back. The black curved structure is a piece of black 1/8" plexiglass superglued to the same size scrubber mesh. It is wedged between the right side of the sump and a thick glass baffle, curving the sheet. A quarter of an inch away from the back of the sump I have a 4.25"x9" heatsink with 10x1w red and 2x1w blue LEDs running on a timer opposite my display lights.


This is a top-down view so that you may see how the water is guided across the bottom of the first chamber toward the back and up the rear panel across the scrubber's surface. There is about an inch above and below the scrubber sheet to allow the water in through the bottom and out at the top.



The main reason I planned my scrubber this way is because I could not afford running an extra pump for heat reasons and wanted to take advantage of the water's momentum coming from the display tank. I also got sick of cutting and replacing zipties every week. The plexi/scrubber sheet has a slight natural curve now that makes it very easy to take out and wedge back in. BTW I've taken gobs of green of this scrubber and I'm finally happy with the design.
 
Last edited:
how do you know if the opening is too narrow? I think mine might be. When i try turning my pump up the water starts to squirt out at the ends. I shut the pump back a little so i didn't end up blowing my cap off, or restricting the overflow so much that the back chamber actually overflows.

I want to widen the opening but im afraid of going to wide and not have water flow evenly across the screen
 
Do you think it is more beneficial to have the lights on for 6 hours then 2 off repeating for a 24 hour cycle? Or do you think it would be better to do 18 on and 6 off?

My thoughts with the 6 on and 2 off is that my water would be "filtered" more often. Allowing a growth period while it is day time.
 
Pics of your setup would help. The text description isn't very clear in my head

this is the setup. the pipe has since been leveled off. i feel like my slot in my pipe may be too narrow. the water doesn't flow evenly across the screen so when increasing the pump speed i thought the flow would "fill in" across the screen but it didn't. it just forced the water to squirt out on both ends of the screen where the slot is the widest

 
Do you think it is more beneficial to have the lights on for 6 hours then 2 off repeating for a 24 hour cycle? Or do you think it would be better to do 18 on and 6 off?

My thoughts with the 6 on and 2 off is that my water would be "filtered" more often. Allowing a growth period while it is day time.

This seems to be the case for freshwater setups, I have one guy that runs 3 scrubbers all on FW and he does this, he says it works much better, but FW scrubbers are quite different in many ways.

this is the setup. the pipe has since been leveled off. i feel like my slot in my pipe may be too narrow. the water doesn't flow evenly across the screen so when increasing the pump speed i thought the flow would "fill in" across the screen but it didn't. it just forced the water to squirt out on both ends of the screen where the slot is the widest


Ah, I gotcha now

Did you cut the slot pipe with a dremel after marking it?

What I've come to learn is that the pipe will pinch closed as you cut it. So if you start on one end and follow the lines you drew, as you get finished the pipe will want to "close", which results in the middle being narrower than the ends. This seems to happen more with Schedule 40 pipe, so I use Schedule 80.

Then I found that it was still happening on S-80 when you got over about 6 or 8 inches, and that was when cutting on a table saw (by lowering the pipe on the running blade). So now I have a router jig and I make a double-pass, one for the primary cut, the second to trim out the closure.

What you could do with your slot is re-mark it from one end to the other, now that the pipe is "pinched" or "closed", you can trim it out and it will stay that way.
 
This seems to be the case for freshwater setups, I have one guy that runs 3 scrubbers all on FW and he does this, he says it works much better, but FW scrubbers are quite different in many ways.



Ah, I gotcha now

Did you cut the slot pipe with a dremel after marking it?

What I've come to learn is that the pipe will pinch closed as you cut it. So if you start on one end and follow the lines you drew, as you get finished the pipe will want to "close", which results in the middle being narrower than the ends. This seems to happen more with Schedule 40 pipe, so I use Schedule 80.

Then I found that it was still happening on S-80 when you got over about 6 or 8 inches, and that was when cutting on a table saw (by lowering the pipe on the running blade). So now I have a router jig and I make a double-pass, one for the primary cut, the second to trim out the closure.

What you could do with your slot is re-mark it from one end to the other, now that the pipe is "pinched" or "closed", you can trim it out and it will stay that way.

i never marked it off other than two spots for the length of the screen. so i guess running the tool back through to maybe clean up the pinched off parts would be a good idea

this is the tool i used
http://www.milwaukeetool.com/power-tools/cordless/2426-22
 
I lowered my pipe on a table saw blade set really shallow. The first pipe I made was with a dremel and I found that widening the gap using a wood file was perfect (at least for my pump).
 
This is my one screen that is perpendicular to my light. Growth is about 2 weeks, second cleaning on a new tank.

I forgot to take a pic of the larger screen, light seems to be working really well. Again, my screens are one sided in the overflow.

 
Nice. I just got two 10 watt lights in last week. Going to rig up a box for the scrubber and see how they work out...
 
this is the setup. the pipe has since been leveled off. i feel like my slot in my pipe may be too narrow. the water doesn't flow evenly across the screen so when increasing the pump speed i thought the flow would "fill in" across the screen but it didn't. it just forced the water to squirt out on both ends of the screen where the slot is the widest

what could i do to add a splash guard to this set up?
 
Back
Top