Maximum humidity

[bystander]

Greetings,
So I have a closed terrarium (kind of...) with a hygrometer, which reads 80-90% humidity through the day. I have few Venus fly traps, two sarracenias, a nepenthes "Sp" (hooray...) and a sundew, which obviously come from different habitats with different conditions.
My question is, (and I tried to google this but everything was about the minimum humidity) can the humidity be too high for some of these plants?
* The terrarium is like a wide flat pot filled with a sphagnum mix, with few bamboo sticks in the center and a clear transparent plastic sheet on top, sort of like it's a tent. (long story...)
Thanks in advance

[ICPS-bob]

Humidity should not be a problem, but limited air circulation might be a concern. Also, the VFT and Sarracenia will need a winter dormancy.

[hcarlton]

Save for the Nepenthes (and even that may not be an exception; if it's the common ventrata it's bomb-proof) all of those can be adapted to very, very low humidity without issue, and the bigger concern will be getting them the light they actually need inside a covered environment. The full sun that at least the Dionaea and Sarracenia will want will cook them inside any enclosure, Drosera do best with very high light as well, and Nepenthes do better with fairly high light overall as well. As Bob alluded, high humidity and an enclosed space means lots of water in a stagnant environment which invites disease and possible death of the plants.

[bystander]

Yes I am aware of the winter dormancy requirement and will cross that bridge when we get to it.

As for light, the display is in my living room, which gets full direct in the morning and very bright light for the rest of the day, the maximum temp according the combined thermometer/hygrometer was 29 degrees Celsius.
And yes
I will add few holes for a bit of circulation.
Actually I never intended for the display to be closed but in two weeks I will be leaving my apartment for another two weeks and wanted to try a way to keep the plants humid while I'm away so that's why I went with the plastic thing, other that the issues you described all is good. Before that humidity ranged from 75% after misting to around 55% in an open display in my living room.
Thanks for your replies

[coline]

Ventrata and most ventricosa relatives rot very easily if they have too much water