Just bought the Dolphin Deluxe 4, yesterday, Opened the pool, bottom covered with alge. I vaccumed to waste and cleaned most of it up. Put the dolphin in, and sometimes it would run for a few minutes then just stop. I cleaned out the filter bag several times, put it back in the pool, and it would not run. I made sure the setting was correct on the handles and the base. Again removed it from the pool cleaned the bag and did the same thing. The manual that came with it is worthless. Any ideas? Did I happen to get a bad unit? Is there any restrictions on pool chemical imbalance for this to run?