Yeah, live algae will plug a DE filter very quickly.

I have very clear memories of a night spent babysitting a 300,000 gallon commercial pool with a below water-level vacuum DE filter. They were preparing to open, and had let algae get started. The filter would plug in 15 - 20 minutes, and have to be cleaned or it would start draining the pool. It was a great system when it worked, but a total pain the rest of the time.

You'll get much longer filter runs if you will KILL the algae. If your stabilizer is not too high, a 10 - 20 ppm dose of chlorine will usually do it.

PoolDoc