[nikhsub1]

Bigben you are right about Eheims being "the best". Although I do think they are the best in terms of failure rate and leakage. Although your valve idea sounds interesting, I don't really want to be the guinea pig. All I am after is the best possible temps with H20. Like I said, the 1250 "seems" to be the pump of choice and I figured there must be a good reason, seems I shouldn't go figuring. To add even more complexity to this issue, I swapped the Spiral for the TC-4 and I am seeing somewhat better results thus far. All I can say is that I will be putting the 1048 back in when I get some time, only this time, I WILL NOT remove the TC-4 during the process so temp differences HAVE to be based on the pump alone. Am I correct to assume this?