Eh sorry not to sopil your sale but CL300 is really no use ina 3 footer tank much less to say a 4 footer....... People get chiller is usuaully because they got themselves very strong lighting that produce lots of heat but with a chiller that can't cool down your tank at all.. whats the use.
MMm BTW i change my CL300 into a CL650 for my 3 feet tank, IMO CL300 is good for only nano tank