Catching RES every two minutes.................... wow. You have them trained like BG.
As far as removing dried FA, it is best to catch it at just the right moisture content. When it is completely wet it is slimy, heavy and hard to handle. If you let it dry completely out it becomes brittle so it breaks up easily and it also sticks to rocks making the collection even harder.
But if you catch it when it is about half dried, most of the moisture is gone out so you do not break your back lifting it. But it is still pliable enough (and not stuck to the rocks hard enough) so a pitch fork (old farm manure fork) can slide under a portion and lift up a big mat then fold it over and get a good big mat to remove.
That is the best way I have found to handle it. Drag it to the edge of the shore line (or in your case just drop the water level), let it partially (but not fully) dry, and remove with pitch fork like a person was handling hay with it.
