how 2 clean overflow????

[saltyESQ]

I have a lifereef overflow that I am trying to clean and eventually sell.

It is filled with coraline algea
how do I clean it?
How do I clean the U-tube?

 

[sharkdude]

soak in some vinegar and water (1 part vinegar/3 parts water). the vinegar is a mild acid that will break down and dissolve coralline, or at least loosen it up.
use a flexible bottle brush on the U-tube.
repeat soak if necessary.

 

[glaudds]

I've used muriatic acid (diluted with water about 10:1). It's available at HD or Lowes in the paint department. Just be careful with it, it's a strong solution of HCl acid.
An overnight soak in a bucket will soften up the crustiest coralline buildup.