) but also.. the ease of flood and drain m8.. compared to mixing nutes by the bucket load daily and daily hand watering its an absolute gift.. stick them in the tray set the timer.. walk away. Daily checks to be done on the vital res figures of course but a lot of hassle saved on the feeding front. Others have had great success hand watering blocks.. @420autoflower for example.. but we're talkin grand master rockwool grower level with my man there.. where as I'm more 'how do u work this ph pen?' Lol
I've had assistance from 420autoflower and @Zaaboot both of whom are very knowledgeable on the hydro/rockwool front and a couple of absolute diamond geezers to boot 
Yes you will have to cal the pen before using it, they should have included a small pkg of cal/buffer solution with your new pen. I try to check the cal once a week just for a piece of mind.
Out the box you should get a little solution and test sachets with it. If you look inside the lid where the glass probe bit sits it slots nicely in to a little foamy bit - add the solution in there, I generally do it once a month or when I remember but it never seems to dry out. At the beginning of each grow I will give it a clean using some cotton buds and a mild soapy solution then calibrate it against 4 & 7, and calibrate again at the start of flowering just to make sure, but to be fair on the thing - when I test it in 4 or 7 solution it is always bang on, and it gets used daily when I am around.
Too true
I own a bluelab and love it. As others have said don't try to pH RO water and calibrate it every 2-4 weeks. As far as leaving it in a probe solution there's a little silicone cup with a foam pad inside the cap that the probe sits in so you just have to wet that. It'll stay moist for a week or two I just add a few drops of solution in there periodically. If you run out of probe solution the pH 7 calibration solution will be the next best in a pinch.@420autoflower @Zaaboot and anyone else who owns a Blulab ph pen.. I assume im gonna have to calibrate it before use?? And all this jazz about leaving it in some sort of solution and monthly cleaning and don't let yer probe dry out (deviant alert hahaha) is this real world requirement stuff or manufacturers blurb?? What are we all doing on that front?? Missiz is still gurnin about the price of this thing
Bluelab PH pens are great and hold calibration for a long time. I’ve only had to calibrate the two pens I have after the initial purchase and was surprised that they were already dead on right out of the box. Never had to calibrate them again but I do use a reference/calibration solution to make sure they haven’t drifted and are always accurate.@420autoflower @Zaaboot and anyone else who owns a Blulab ph pen.. I assume im gonna have to calibrate it before use?? And all this jazz about leaving it in some sort of solution and monthly cleaning and don't let yer probe dry out (deviant alert hahaha) is this real world requirement stuff or manufacturers blurb?? What are we all doing on that front?? Missiz is still gurnin about the price of this thing
