Algae that just won't die!

[Rumpy Pumpy]

I've been struggling with algae on my live rock for some time.

My scrubber produces lots of growth and all my water parameters are good (N & P undetectable)

But still it comes.


So, finally having had enough, I decided to take out the worst of it and put it in complete darkness for a while to kill it off.

So far it's been in a black plastic tank with a lid (and a bubbler and a heater) for nearly a month and there is still green algae on it.

A lot less but it's still there.

Incredible really.

[SantaMonica]

Darkness just puts more phosphate into the rocks when the algae dies and raises P in the water. You want the algae on the rocks to live, so as to consume phosphate from the rocks.

Mine took 6 months to do that.

[Rumpy Pumpy]

This has been longer than that.

But I'm in the (slow) process of changing tanks and revising my system, and I have much too much live rock in any case (I think that's been my problem, I have a load if rock, probably saturated with phosphate so it's taking a very long time to come out)

When I've decided which bits of rock are staying I'll set up a temp scrubber to dephos' the rest before selling it.