The mesh cover allows some light and debris through. However, it is relatively easy to put on and take off. I usually do it myself or with five minutes of help from my wife or son (the whole process takes maybe 1/2 hour to an hour). In NJ, I close in late September or so (I am closing this weekend) and open the pool in late April/early May. I often open the pool, get everything going and, if the weather turns cool again (or if my spring flowering trees are too bad) put the cover back on and add a little bleach through the skimmer every few days. The one time I openned in the middle of May, I had some algae (the water looked a little green) but nothing serious.
The mesh cover does require that you scoop some leaves (and about a million worms) out in the spring and brush and vacuum as pollen and silt coat the walls and floor. I have no experience with a solid safety cover, but after having my dog go right through a regular cover and having kids, I have much more peace of mind with a safety cover.
Hope this helps with your choice.
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