Has any one tried putting an anchor on each end of the dock. Suspended from a pulley, one side of cable with 500 lbs of weight and on the other end say 300 lbs of weight, having the 300 lb weight just 3 feet below dock or half of the depth of the water. Float tanks may need to account for extra weight. That way you could have weight on the very end where it would do the most good. Or if you have a stable water level you could just have the smaller weight set on top of the larger one and it would only move when your water is going out of the spill way. Could be a swimming hazard but not much more than a large rock on the bottom. You may want two pulleys and run cable under the dock so the smaller weight could be on the other side of the dock so it would not be tangled with or around the anchor cable of the larger weight.
By the way your dock looks great!

61 acre water shed lake. bass, channel cat, black crappie, wiper, walleye, redear sunfish, blue catfish and bluegill. To many bullhead and common carp
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