Every year I drag my plants in and out, this year my husband bought me an adorable bubble greenhouse. It keeps condensation in the house , I unzip the door every day . I'm afraid the moisture is going to breed spores any ideas ?
Condensation is always a problem with the plastic greenhouses. You're doing the right thing unzipping the door for ventilation. Apart from that and keeping it clean, there's not much else you can do IMO.
I've had one for a few years now and haven't had a major fungus outbreak yet.
Kitty is right - it's always a problem especially with the smaller plastic G/H's.
As well as opening it up whenever possible, it will help if you are very careful with the watering and also not cramming the plants too closely together if you can avoid it.
And always remove dead or dying leaves and especially flowers promptly to reduce the incidence of grey mould. It often starts on dead bits, but is evil if it moves on to living tissue!
Yes - that's definitely another "must do " as BCdays says.