8FT Pond Filtration Plank 1172mm Length - Complete Kit With Fittings8FT Pond Filtration Plank 1172mm Length Complete Kit With Fittings. This kit enables pipework going to your filtration equipment to be taken through the pond wall and not over the side so unsightly pipework is kept hidden below the water line. 1172mm filtration plank with 2 x 1. 5" diameter holes. For use in conjunction with a 8' Octagonal Layzee Living timber pond and the 12' stretched octagonal pond. Whats included: x1 1172mm filtration plank with 2