African Clawed Frog Tank adjectives set up, but I enjoy a cross-question in the order of filter/breathing room?

I originally had an inch or so of air between the water top and pale in my 20gl tank, but I filled it up to a few centimeters between contained by order to make the "waterfall" from the filter disappear straight into the tank so as to not disturb the frogs. I be wondering if this was ok or not for them because I know they have to come to the top to breathe. Any lend a hand is appreciated.
I own two quetions..?
Answers:    I'm confused. "A few centimeters" is more than an inch.
(1 inch = about 2.5 centimeters.)
Anyway, I'd say an ich of space at the top is good near aquatic frogs. Less than that is iffy. They'll probably still figure out a place to breathe, but I wouldn't want to count on that.
What plant is this ??
You will want to own a little splash into the water from the filter. It helps surrounded by the aeration and water movement and it will help the frogs not bother them. Believe me when I tell you this.
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