Once you get your ato i'd run the water level at the bottom of the skimmer neck, then adjust from there. It will most likely be pretty dry skimmate, so just raise up the water level in the skimmer until your getting a good color of skimmate you like. And keep the skimmer in 8-10" of water in your sump. Once you have the ato set up it won't be finicky anymore. It will be set and forget.