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[c moore]

Thanks for replies, maybe i didn't make my post clear enough.The question i was asking was about the distance between the heat cord & the bottom of the tub in relation to holding good temps. The gap at the top of the tub as stated by some isn't really an issue for me.Mainly concerned with heating.
They just look as though the heating could be more effective with the cord being closer to the bottom of the tub.
Cheers