[jnarowe]

Thanks for the links guys...

"Hi Steve,

The image shows a microalgal growth that is probably a mix of dinoflagellates and diatoms. Such growths also contain cyanobacteria, but as minor component. This type of outbreak is characteristic of new tanks, generally, around 6 to 7 months old, that have inadequate biological filtration as well as nutrient export problems.

These algal outbreaks are, as with cyanobacterial outbreaks, symptomatic. In other words, they are not the problem but, rather, are indicative of the problem which too much dissolved nutrient in the system. Treating these algae or cyanobacteria with chemicals is worse than useless, by killing the algae without attacking the root cause of their appearance in the first place, you simply boost the nutrient level in the system, while destroying large portions of whatever biological filter you have.

To address the problems, you need to reduce the nutrient levels in the in the system significantly. For a plan of attack see the sticky thread, near the top of the forum listings titled, "Red slime algae...."

Yes - I know they are not red slime algae. But the same solution will work in both cases. " --Shimek

Solution:

"We cut the lights for 24 hours, and then every day there after we ramped it up an hour, and now its been running at 4 hours a day for the last week. We're going to start putting it up to an eventual 8-10 hours in the end, but slowly and monitor how things go. If the stuff comes back at all, the light gets cut an hour.

We also started using filter floss between the baffles of the sump, and blew the rocks off daily (sucking this stuff out was a pain, this was easy). The filter floss got changed daily, or sometimes multiple times per day depending on how gunked up it got.

Feeding effectively got cut in half.

And we also increased the flow. Those pictures were days after we added the SEIO 2600. We had a total of about 750gph flow in powerheads, plus the Mag 9.5 for return. This was too low of flow in the tank, but the SEIO 2600 kicked that up a bit, and now things are getting back to normal."

He added that they stopped water changes as well.