it's really hard to put a working time on a heater. It could be anywhere from 1 second to 50 years or more. The nice thing about visitherm stealths is that marineland has a lifetime warranty on them (make sure to get the receipt if they have it, that'll help you big time). If it quits heating, or wont stop heating, they'll replace it for you.
As for switching from sw
, you could probably get away with a good rinse, but if it has alot of build up on it, vinegar will help with that.
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