I concur Z...because that is what happens in my same cloner when it gets too hot...that is the only reason I went 15/15 and eventually to 45/15,,,just to let the pump cool, and since that...Mine quit rotting...lw

Another idea would be to put in bulkhead style drain in cloner and set on bigger rez (an 18 gallon tub is great) then it would stay cooler...put pump in bottom rez and pump to cloner...just ideas. later lw