i should of asked this a while ago but i thought i was good - for the milwaukee orp controller probe, are you suppose to submerge the whole probe, or just have the tip of it in water. ive had it in the setup for two weeks now, fully submerged close to the bottom of the tank. after the first week i cleaned it in vinegar and placed it back in the tank. mid into the second week the meter read 800. it was cleaned again returned. today it read 482 (no ozone has been run during this two week period). when i removed the probe however i noticed rust on the top of the probe, where the cord meets the probe. was this part not suppose to get wet? if not then i definitely feel silly? would this cause the wild readings, or not? it was working fine the first week. thanks for reading this.