If you have the cover curling-up the wall at its edges, simply create two 100mm slits in the cover edge in front of the skimmer box. The resulting “flat flap” will quickly drain excess rainwater to the skimmer box. They are also good in terms of retaining the heat better https://josuecwnyh.bmswiki.com/3530267/indicadores_sobre_cubierta_de_piscina_que_debe_saber