Ok from the info I have gathered here to budget on annual feed costs the rule of thumb is -

2 bags of feed per month per feeder, feeding 9 months per year at a rate of 1 second feed @ 3 times per day. Feed cost at $ 35.00 per bag.

Annual cost and number of bags of feed = $ 630.00 / 18 bags.

So my 9 acre pond with 3 feeders should budget = $ 1,890.00 / 54 bags.

Thanks.

Dave