scrubber flow ,screen size, light, circulation

[Nick28]

7 days from cleaned screen

-lights 9.5 watt 2700k cree led bulb 120 degree spread 14 hours on
-size 48 sq in
-circulation 224 GPH calculated for head loss
-11x tank volume per hour
-Above tank filter

I haven't posted in a long time. I've been tinkering with scrubber designs and i think total system flow is important for the scrubber to get working (more so than lighting).

It just makes sense that the more molecules of N:P:FE per second the better it will grow. I got the idea from green algae growing on my mp10 pump that wasn't getting direct lighting but plenty of flow.

was originally using a 19.5 watt 2700k 25 degree angle for the first week but the center was way too intense nothing grew and mostly yellow grew outside the circle
5968

[SantaMonica]

Looks like it need more air/water turbulence at the growth surface, in order to deliver more nutrients to the growth. There should be no standing water on top of the screen; only fast moving turbulence. Since it looks like the screen is under water, without air/water interface turbulence, the boundary layer is not broken away from the algae and the algae thus cannot get enough nutrients out of the water even though a lot of water is flowing through. The boundary layer is keeping nutrients from reaching the algae, and thus the light is too bright relative to the nutrients it is getting, thus burning in the middle.

More water flow does not remove the boundary layer around the algae as well as air/water interface flow:

http://www.algaescrubber.net/WhyBubbles.jpg




For a horizontal river, this is done by keeping the screen right at the wave surface at the top.

[Nick28]

the bulkhead on the bottom right of the picture is closed off ( from another design). it actually drains from underneath theres about a 1 inch gap of air under the screen water runs off the sides and drips threw

If i can find the venturi part to the maxijet i was going to put that on so air bubbles would poor out on to the screen.

I've noticed when the tank water evaporates and the pump starts sucking in air it turns the surface of the screen soapy.

[Nick28]

the flow is very turbulent the water slams the center of the screen , flattens out and expands evenly

i'll try and get a video this week

algae in the display tank is disappearing very fast, cheato disintegrated, and little calcifying white things are exploding all over the place

[SantaMonica]

Well if you can reduce the light, it should probably grow thicker.