mine also same batch... both Roidan and Ivcap asked me where i got my chiller .. You really very unlucky to kena this.. somemore change already still the same... so in the end how? He left without doing anything? Just say your pumps hot and left? It definitely cannot be the case....
My 4x2x2 with ocean runner 6500, ocean runner 2500, extrema, ehiem compact 600 and PL lights(damn hot).. also can cool down to below 27 relatively fast... maybe i shall try cooling it down to 25 see how long it takes...