I'm using quite basic equipment and thought everything was ok when I did my first transfer from grain to substrate but I forgot how tricky my heat source is to calibrate. Overnight the temperature crept up to 38°C. Should I give up that batch now or could it still be alive?

should be ok,think it is over 40C for some time to kill the mycelium

happened to me once,the heat matt was directly under the tub/chamber,it is good practise to keep it elavated about 0.5cm above the chamber

chop sticks are good or anything similar, place them onto your matt and put your fruing chamber on top of that

Phew! ok, thank you for giving me some hope. I'm using some water filled sandwich bags for thermal mass and separation between the heat mat and the substrate. Note to self and other mushnoobs: easy temperature control is worth the expense.

Are you talking about adding your colonized grain to your pasteurized substrate or actually pasteurizing your sub?
If you are talking about spawning to bulk and you're growing cubes, I've found that if you find the room temperature to be comfortable so do they.

I see that you posted that on the 7th what happened? I'd like to talk mushies on a platform that's less silly and more respectful than the shroomery.

Thank you Kingwhatt - I can relate to wanting a more serious and productive discussion about mycology. Well... True to noob-form I made a few more mistakes. Like assuming that the sealed packages of coco-coir and vermiculite that came with the kit were ready to use. So my B+ strain has done it's best but only barely managed to pin here and there in all this time. The temperature and other environmental conditions here don't seem all that conducive to this new found hobby and I'm currently procrastinating about buying and building more equipment to compensate for that. I'm having to go from zero to keen amateur in one step...

you really don't need to buy much if you're resourceful its a great hobby for poor pepole. good luck friend.

Agreed. Do stick with it once you get everything working you will figure out the process is much less involved than it seems at the start...

I only just started too but I think it becomes easier to adapt for your specific situation and conditions after one successful run.

Thanks for posting. Reminding me I should try again. I tried to spawn to bulk from rye grain in two big mono tubs and both failed. You got a better result than I did. I think I opened the tub too much before the substrate colonized.

So this time I am going smaller and simpler to get some success first.