The problem with feeding too much is that you're adding extra nutrients into the water. Not only from uneaten food, but also from extra fish waste from the extra food they're taking in. This could be mitigated be having great pond plant life established to soak up some of those nutrients. I also yearly stock tilapia to aid in algae consumption, but in Ohio they die every fall/winter so I don't have to worry about them overproducing, I'm not sure how that goes in your area. You very well may not be overfeeding, as ewest stated, their feeding should pick up as water gets warmer, just something to keep in mind.

As for pellets floating to shore, I'm not sure how big of an area you feeder throws to, but I made a large circle with 1" black poly water line and tied it off to my dock. I just hand feed, so I throw my feed into the circle so that it minimally gets splashed out of the ring. If you don't have something to tie it off to, you can also anchor it with enough line for the ring to float.

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