Opinions will differ, and I know it's not ideal, but putting the tabs in the skimmers seems fairly harmless - I do it myself. It might be dodgy if the associated pipework was made from something other than UPVC, whch is fairly easy to identify.
I think using a floating dispenser is pure guesswork, unless you monitor on a daily basis. I wouldn't assume that the number of holes uncovered relates to much at all.
Dave
Hi If you have a liner pool the floating dispenser will leave you with white stains from the clor taking the colour from the liner, they tend to get stuck in one place and the clor dispenses directly below.
In 17years of pool installation i always advise to put all chemicals directly in to the skimmers
hope this helps
Chrish
I lost my internet connection so apologies if I end up making two posts.
There are a lot of people who put their galets in the skimmer but be careful particularly if you have a liner pool as when the pump is off you are allowing a lot of chlorine to build up in the skimmer and then you are injecting a high dose into the pool when the pump comes back on. If you find yourself in a situation where you need to shock for example, you are better doing it in stages and keep your pump running for the entire time the tablets need to disolve.
Please note that any unsolicited advertising will be removed