hi all, having recently moved onto all-grain, I've decided that I need a more accurate thermometer than the cheap glass one I've been using until now... in an ideal world I'd pick up a waterproof Hanna one with separate probe so I could monitor my mash without opening the boiler (I practice BIAB) but don't really have £150 to spend. I've seen the Hanna 'CheckTemp' one piece probe thermometer on eBay for £18 second hand, or a tenner more shipped from Germany... would this be suitable, or should it really be waterproof? And are there other more affordable makes I should be looking for? Thanks in advance :)