Particular attention should be paid to critical places — the joints of the bottom and walls of the bowl, where it is necessary to stick sealing tapes. Well, before you do tiles or mosaic, the bowl must be checked for the presence of leaks, filling it with water and withstanding it 10 days. And after draining the water, the bowl must be reduced, otherwise, in the presence of small sand and other contaminants, the tiles will not be glued enough.