Changing the subject slightly, I have a pump out on my boat that has a holding tank in the engine room, some way from the macerator toilet, that just got blocked, its taken me all day to clear. The pipe work is in hard plastic but I used the wrong elbows, should have used sweeping bends my fault. Any way it turns out that the pipe work was full of scale so had to tap pipes to loosen scale with small hammer and use a wet vac to suck it out. Now working fine. I tried putting a peace of scale in a jug with some descalant but it did nothing. Does anyone know of some descalant that can be left in the pipe work over night that will dissolve the scale.
Thanks Fred.