To diagnose and fix a pool-skimmer leak, is about 1 inch higher than where the skimmerbox meets the pool wall. of underwater pool-repair putty from the Rob Cox. by Rob Cox, May 20, 2011 PoolSkimmer Care & Repair Tips. P ool skimmers come in many types and sizes. Some are free floating in the pool, but most pool skimmers are attached to the wall of the pool. With the pool pump off, remove the cover to the poolskimmerbox. The pool water level must be above the area where the skimmerbox meets the pool wall. As a swimming pool leak detection and repair expert, I wrote this website to educate the reader with all there is to know about the swimming poolskimmer. My easy pool leak repair by Jon Claerbout If you are lucky, your pool leak repair will be as easy as mine was. The skimmerbox is plastic, Cracks or breaks in a poolskimmer can waste a lot of water; fortunately, leaks in the skimmer are easy to fix with epoxy putty and silicone caulk. In New Jersey a new skimmerbox for an inground swimming pool can cost an average cost of $1500 or more to replace it, not to mention new tile work if needed. Pool Fountains; Pool Lights; Pumps; Cover Repair & Replacement; Safety Cover Accessories; SkimmerBoxes; Solar Heating Systems; I have a crack inside the skimmer wall. The previous owner repaired the crack, I can see white putty like material along the crack line. The skimmer is leaking now again. Pool Info: Swimming Pool Skimmers. A wooden box or form is then built around the skimmer, pool putty is used to repair cracked skimmer throats and wells.