i agree the Red Sea ATO is kind of high, it is really difficult to refill. What I did, I have another portable 4 gal ATO container to fill the Red Sea ATO. The liquid sensor is sitting on the Red Sea ATO.
here is my journal , i have some more updates need to be posted. Thanks.
https://www.bareefers.org/forum/threads/spongebobs-rsr-350-journey.27469/#post-401757
I ordered online but turn out I cannot use all of them. Free to supporting member. if you have soft coral frag to trade that will be nice, otherwise it is free. Thanks!