My display tank was fine because it is a reefer with a chiller apex etc but my nano (20g IM peninsula) suffered since I accidentally set up the ato with reverse flow. When I came back, luckily no flood by my tank had half the water and all fish except my red hi fin goby was dead. Half my inverts and all my shrimp and my lps corals all died. Not sure if I should just put the goby in my reefer and call it quits. It was an expensive endeavor