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I agree with Mass: most Avicularia love to build their nest almost against the ceiling of their enclosure. Which means yours could be staying against the mesh a lot of times... with the danger of claws/fangs being trapped in it. But it's no problems to replace it by what Mass said: one piece of acrylic with some holes drilled (small holes...) in it for ventilation.About your enclosure, if it's for an Avicularia (is it?), I'd personally put more vertical cork barks (from bottom to top, or almost), maybe some vertical plastic plants (for the height) so that your Avic can build its home in the height and have a lot of places to anchor its webbing. Try arranging your enclosure so that you have a lot of possibilities for your T to web close to the top of the enclosure.
I agree with Mass: most Avicularia love to build their nest almost against the ceiling of their enclosure. Which means yours could be staying against the mesh a lot of times... with the danger of claws/fangs being trapped in it. But it's no problems to replace it by what Mass said: one piece of acrylic with some holes drilled (small holes...) in it for ventilation.
About your enclosure, if it's for an Avicularia (is it?), I'd personally put more vertical cork barks (from bottom to top, or almost), maybe some vertical plastic plants (for the height) so that your Avic can build its home in the height and have a lot of places to anchor its webbing. Try arranging your enclosure so that you have a lot of possibilities for your T to web close to the top of the enclosure.