HOG upflow algae scrubber build

[Henchman24]

I started building a HOG (hang on glass) upflow algae scrubber a couple months ago & It is finally starting to get somewhat decent growth on it. I wanted to share some pictures to show how the HOG is different from the waterfall type scrubber.

The HOG has a wetside which goes inside the tank against the glass with the screen that the algae grows on. It also has a dryside with a light that goes on the outside of the tank against the glass.

Build Process
I started with two pieces of black acrylic that will be used to create two half boxes. One for the wetside & one for the dryside.

Using weld on #3 & Then #16 to fill in gaps I put the half boxes together. You can tell by the way the pieces are cut out they won't match up perfectly as two of the sides should have been cut 2 times the acrylic thickness shorter to fit together properly. Basically the two halves don't have to be waterproof or lightproof but it would have looked better If I took the time to cut them.

I am going to break this up into a few different posts so stay tuned for more:

 

[Henchman24]

Wet side half
I wanted to make the mesh screen that the algae grows on easily removable. I want to be able to pick the screen up out of the sump & carry it to the sink for weekly cleanings without having to undo any zip ties holding it in place so this is how I achieved that.

The screen mesh is attached to a clear acrylic piece that slides in & out of the wet side box
cutting hole in clear acrylic

clear acrylic with hole cut out

clear acrylic with mesh screen attached

screen sitting in black acrylic box - slot cut for clear acrylic piece

In the upflow scrubber as the name suggest the water flow moves upward by an air stone. I attached the airstone using fishing line.
holes were cut at the bottom & the top of the black acrylic box

I attached some suction cups to hold wet side against glass

this is how wet side looks sitting in sump

 

[Henchman24]

Dry Side
I wanted to use Led's for the lighting. I used 32 of the red 1 watt led's which is probably overkill so I only have them come on for 6 hours a day at the moment until I figure out what work's best. I may actually get a power supply that I can input a 50% duty cycle square wave into so the led's can be on almost all day long. I just don't want to burn the algae by having the lights on too long with the current setup. Once I get a good thick algae growth I plan on slowly increasing the time the led's are on. I am using 10 watt ceramic resistors as well as multiple surface mount littelfuse fuses.

Led's soldered to perf boards

led boards in acrylic box

led's powered up

Algae Scrubber glow in Sump

 

[Henchman24]

Growth Pictures
The first few pictures were taken approximately every two weeks & the last few once a week. The growth rate was slow at first which I believe is due to the air pump I was using was small so The water movement was slow. I increased the air pump size & the algae growth increased quite a bit.

two weeks

4 weeks

6 weeks

7 weeks

 

[rompininphx]

Awesome job. What size air pump are you using?

 

[Henchman24]

Awesome job. What size air pump are you using?

I am using an Aqua culture MK-1504 which has two outlets but I have them both connected together with a t adapter going to 1 airstone. That air pump is recommended for a 20 to 60 gallon tank. Before I was using a whisper 10 which is recommended for a 10 gallon tank. There is a Big difference in the amount of air coming out of the air stone between the two. I guess It is a matter of playing with air flow & lighting period to get decent growth. I am curious if a powerhead would work as well for water movement compared to the airstone or if the air helps in the algae growth. In any case it should be lowering the nitrates & reduce unwanted algae growth in the display tank. I was getting frustrated because it took so long to start growing algae.

 

[1panman1]

Just curious as to the cost to DIY versus purchasing a pre made one from Santa Monica filtration?

 

[rompininphx]

You can make one for less than $20. I used a silicone type basket from a craft store, cut the bottom out and attaced a screen and airline tubing. I attached suction cups to hold it to the glass and am using a red led bulb from ebay on a clamp fixture for light

 

[Henchman24]

Just curious as to the cost to DIY versus purchasing a pre made one from Santa Monica filtration?

A DIY one is going to be cheaper. The Santa Monica HOG scrubbers start at $100. I spent about $60 to make this one & it is twice the size of the Santa Monica one. You get what you pay for though. I saved money but spent several hours building this & with DIY there isn't any warranty if it breaks.

You can make one for less than $20. I used a silicone type basket from a craft store, cut the bottom out and attaced a screen and airline tubing. I attached suction cups to hold it to the glass and am using a red led bulb from ebay on a clamp fixture for light

I watched several youtube videos on building the cheaper $20 varieties when planning this one. One guy used two empty tv dinner trays for the containers which was interesting.