Hi. I've bought the Impey formed tray. Looking at tanking kits, the Impey one (roll out membrane) would cost me about £450 while an alternative liquid kit, by Everbuild Aquaseal will cost me under £100. (15 sqm). Do I just treat the formed tray like any other floor when applying the liquid membrane, in other words, do I just tape over any cracks/joins then paint it on? I see that the aquaseal kit comes with a small piece of non-liquid membrane to fit around the waste. I'm just checking I'm not doing something stupid! Thanks.