Clear Growth

[SantaMonica]

Enclosed upflow scrubbers like the SURF2 can pull a lot of nutrients out of the water because the enclosed water circulates around and around before exiting the box, however if iron is low, you may get clear growth like this:

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

[Greenchaos]

Isn't iron always going to be low, if the water goes "around and around before exiting the box", same principle as accelerating algal growth by artificially reducing nutrients in the box?

[Greenchaos]

Come on Santa, it's not rocket science? I know you've seen my reply, why ignore it. As a newbie it seems like you ain't got an answer.

http://i1269.photobucket.com/albums/jj597/Garf1971/33cb01e764bd53fbcb15b0b2556331ad_zpsd53728e2.jpg

[SantaMonica]

No, iron is not always going to be low.