Recommend get combo or hygrometer ASAP. Once you have it, if need to raise humidity can use aluminum foil to cover the top metal screen partially. What I do is cover the whole top; then using a sharpie marker place light fixture on top and make an outline. Then using scissors cut the opening just a bit larger than light (maybe an inch around it). That will raise the humidity and will probably work with one or two sprayings a day

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