So - my bullfrog has been upgraded into a bigger tank, which is largely water, with a large platform with fake plants to hide under. Inside the water I've planted a bunch of live aquarium plants - which I've been reading I should dose with CO2 to help them grow. But my tank has a solid, acrylic top with two notches cut (about 2" by 2") cut for power cords and tubes. If I'm running a DIY CO2 system (2 liter soda bottle + yeast) in a 50g tank, with 10g of water in it and 40g of 'air,' can the CO2 reach a dangerous level for my frog? Should I switch to some sort of screen for the top of the tank instead? I was hoping to keep the solid top, as it traps humidity and conserves moisture, which I figured was good. Bonus question: the condensation on the side of the tank makes it hard to see my frog. How do you fix that? If I take the lid off, it evaporates away and solves the problem, but deprives Jhermy of the bonus humidity.