Hi
A skimmer is absolutely essential Does more for water quality that all the other equipment combined Now we could argue all day about sizing and flow rates. Another method is to use "Ozone" rather than air which adds a sterilizing effect to the mechanics.
They won't elinate water changes since you need to replace elements consumed by the inabitants as well as stripped out by the skimmer.
All one needs to do is look at the smelly nasty looking stuff that is deposited in the cup lol
They are doing a LOT !! gary

The skimmer basically went crazy because you put your hands/arms into the tank. The oils from you skin disrupt the functioning of the skimmer. you also added corals which cause th bioload of the tank to increase. It should settle down in a few days.

Protein skimmers are great, but yet a bit of trial and error to adjust. Many reasons why it would do that, as already said.

If you have not already found the site, I believe the best information you can find is at reefcentral. Many very experienced water keepers. You also never said what skimmer you have, that sorta makes a difference. My Reeflo Orca goes crazy with any little difference. Hands in the tank, goes crazy. I just don't recommend cleaning the main chamber as it needs to build up a "scum" layer. Well, depending on the skimmer. Check out the site, loads of info there.