all from my experiences
my friend has that cloner, personally i run a diy aerocloner
I think you can run a flooming pump in there too, and it gives you something to do it with
smaller clones generally root quicker for me anyways, big ones take longer and for some reason lose a few leaves
I make sure and use sharp, sterile scissors for the cuts, and it works great. I could use a disposable scalpel, one day..
you are supposed to change the water once 2 or 3 days after putting clones in, because if any plant matter gets in the water slime forms. Changing it allows a rinse off of the stem too, and gives it new fresh water that shouldn't go bad
i keep water around 68, try to keep it below 71. 65 isn't too bad but that's where i try to keep it. It's easy though for me cause its a 14 gallon reservoir instead of 2 cups lol
also i'm pretty sure you just make sure they're low enough so the bubbles are popping and the mist from them is hitting the stems
I like my aerocloner though, but it's way bigger and i see the advantages to a simple cloner like this.
don't forget to clean that thing well. I use a nylon brush (toothbrush or toilet brush) to clean it with a little soap and bleachy water. I then rinse it very well and dry it, and store it for next use.
all stones and hoses and whatever are soaked in hot bleachy water and scrubbed off then rinsed as well