Most all of the responses here are right on.
1) Get rid of the waterfall.... it's a haven for bacteria.
2) All screen cage
3) You have a montane species who typically likes cooler temperatures and a lot of water and humidity. Some montane species like to drink right from your sprayer if you hand spray. They get a lot of water this way. Keep this in mind.
4) Offer a basking light of a lower wattage (50-75 watt), lots of foliage, and they can regulate their own temperature needs this way.
5) I doubt Walmart has a UVB bulb for reptiles. I'd recommend either ordering online or going to a petshop that sells reptiles. You should be able to find a Zoo-med UVB bulb for your florescent light fixture.
6) Two crickets in the morning and two in the afternoon probably aren't enough for their diet needs. Add variety to their diet and if full grown adults, I'd recommend at least 5-6 full grown crickets a day.
7) Use a good gutload to feed your crickets and worms. Wild-Eye Reptiles has a good gutload for a decent price and good service. Add vegetables to your feeders as well (carrots, kale, broccali, etc). This helps provide good nutrients to your chameleon and it also provides a water source for your feeders. What your feeders eat, your chameleon eats

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You've come to the right place! Good luck on your new chameleon

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