his bitch is just to big & top heavy to lift out of the tent & do a res change ,so she can feckin stay there ,Ive emptied the res as best i could with the level indicator tube tipped in to a can ... topped up again with plain water & emptied again... Then added the Overdrive res mix Its only one res & then on to flush so i guess its ok ..Anyway,res change done & shes now on EC-1.6 ...PH-5.9 ... OD - carbo & aqua .