Nils, I start up my aerator a little at a time in the spring like ewest said. The first day I run it for 15 minutes, 30 minutes the second day, 60 minutes the third day, 2 hrs the next (doubling the time each day) etc. The whole process takes about a week.

If your pond is older with a lot of muck you should pay attention to how it smells while the aerator is running at startup. If you still notice a strong odor when pumping on the third day, I wouldn't double the running time until things improve. If you notice the odor is gone then you can continue on doubling the time.

If you run your aerator 24/7 during the spring/summer/fall season you should get less muck buildup reducing chances of a winter kill and an easy spring startup. I really didn't notice any odor when starting up my diffuser after last winter but my pond was re-dug 2 years ago and is still pretty new. I also add beneficial bacteria during the season and I haven't noticed any muck build up yet.



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