"Scrubber"/refugium concept - Thoughts on this?

[Rumpy Pumpy]

I have an idea to convert my sump to a large flat algae growing area something akin to SMs new floating scrubber but much larger.

I'd have a false raised bottom/screen with a rough surface & with nylon ribbons attached and air/water mix provided by air pump &/or small power heads with venturis. Light would be provided by led grow bulbs in pendant fittings suspended above.

The idea being to allow the algae to grow in 3D, across a wide area, providing a refugium for pods & what have you and also to export nutrients by the occasional manual removal of some of the algae.


Pitfalls?

[SantaMonica]

It will work if you have enough bubbles flowing up the ribbons.

[Rumpy Pumpy]

Thanks SM.

So I guess it'd need quite a hefty air pump to cover a larger area.

Maybe the venturi idea would be better.

[Rumpy Pumpy]

1st attempt

Bit rough & ready. The canvas screen is pre-grown so already green (this is day 1). Used some spare bits of rock to weigh it down

Couple of venturi powerheads provide flow and bubbles (plus air/water mix from the DT overflow)

Lighting is 2 x 15w cfl spots (will be replaced by 2 x 15w led grow bulbs when they arrive)


Vid here if anyone's interested

http://youtu.be/XduaCHIDO9s

[SantaMonica]

I think what's going to happen is that the screen is going to block bubbles from reaching the middle. Maybe you can cut holes in it, and add ribbons.

[Rumpy Pumpy]

Not sure I follow. The screen is on the bottom of the sump, the bubbles are blown across it by the venturis.

[SantaMonica]

Might work then.

[Rumpy Pumpy]

Well that wasn't very successful. There was a little 3D growth but not anything like as much as required (left it for 9 or 10 days)

So this is the version 2 (video quality not good, but you can see what it is)

http://youtu.be/eZtNi_zs5qw

I nicked Garfs cable ties idea and relocated the powerheads to one end of the screen. The overflow from the DT now discharges around the powerheads so that they suck in some of the air mix and blow it out across the screen as microbubbles.

2 x 15w CFLs replaced with 2 x 15w LED grow bulbs.

No idea if this will work but here's hoping.