Good idea, bad in practice

We were asked by an owner of a stone multi tiered fountain can he install a UV in the base? Below for EXAMPLE ONLY! is a 3 tier fountain.

The idea was to install a UV (The same as pondkeepers use) in the base of the fountain with the object being to keep the water clear. The UV unit was to be hidden in the base of the fountain.

Can you think why its  bad practice?

First you have to find a UV that will fit in the base, then you have do drill hose sized holes through the last bowl (would you want to do that on an expensive feature) and you have to find room for the pump, then you realise that a UV only causes the algae to clump together, so you need a mechanical filter (Just as pond owners have) so where is this going to go, then you have condensation, this will cause the foot to fill with water and in a frost it will expand splitting the foot. Is it really a good idea when a "chlorine" or "Bromine" "pill" can be added with no hassle.