I have never, in fifty years of managing tanks---had this happen.
ONE and only one hose goes from my autotopoff to the sump. ATO brand topoff. The pump for this hose sits in a 28 gallon barrel, which had a little room at the top. Decided to discard some water from the saltwater-making barrel (since it was run on some ro/di filters needing changing) and send it to the topoff barrel. I sent over about 10 gallons to the topoff barrel, pure fresh water, and...
The ATO unit delivered 10 gallons of fresh water into my 120 gallon system.
Naturally this threw the salinity in my tank from 1.024 to 1.007 or 17---I was too busy trying to figure out WHAT happened to try to squint sharper and be sure. It's not good for a coral tank. I'm not worried about the fishes, but I am NOT pleased in general. I'm 2 mixing days away from a general water change, and my salt doesn't get here til Wednesday, after which I can begin to do something. Meanwhile---we just rely on evaporation.
The black magic part involves---WHY in heck did the topoff unit commit suicide by drowning. The sensor is an inch under water---and there is ZERO water source for the sump except the freshwater barrel into which I injected 10-20 gallons of fresh water.
Water pressure increase kicking the ATO from the wrong SIDE of the transaction? It's set on ONE in-tank sensor, HAS no limit sensor set or plugged in... Or could it be darker forces?
ONE and only one hose goes from my autotopoff to the sump. ATO brand topoff. The pump for this hose sits in a 28 gallon barrel, which had a little room at the top. Decided to discard some water from the saltwater-making barrel (since it was run on some ro/di filters needing changing) and send it to the topoff barrel. I sent over about 10 gallons to the topoff barrel, pure fresh water, and...
The ATO unit delivered 10 gallons of fresh water into my 120 gallon system.
Naturally this threw the salinity in my tank from 1.024 to 1.007 or 17---I was too busy trying to figure out WHAT happened to try to squint sharper and be sure. It's not good for a coral tank. I'm not worried about the fishes, but I am NOT pleased in general. I'm 2 mixing days away from a general water change, and my salt doesn't get here til Wednesday, after which I can begin to do something. Meanwhile---we just rely on evaporation.
The black magic part involves---WHY in heck did the topoff unit commit suicide by drowning. The sensor is an inch under water---and there is ZERO water source for the sump except the freshwater barrel into which I injected 10-20 gallons of fresh water.
Water pressure increase kicking the ATO from the wrong SIDE of the transaction? It's set on ONE in-tank sensor, HAS no limit sensor set or plugged in... Or could it be darker forces?
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I think the trick lies in the fact this (despite my try at buying a single-action ATO, ie, just fill the confounded water level to here, nothing fancy!---) is a dual function--deals with high and low water, so it won't run your source dry. I don't CARE if it runs the source dry---it's a bucket. But---the ATO doesn't know that. So somehow it got super helpful. It took me a while to figure it, but if an ATO is capable of either A or B and gets screwed up, the mere fact that it's capable of B likely means ---it did B.
