One of my tanks (29 gal) contains 4 fire bellied toads. The set up is a false bottom with a water area and a 'waterfall.' I usually do water changes weekly.

I syphon the water out, to the best of my ability, a small amount will always remain. I then add a gallon of distilled water to the tank, and syphon it out again.

I then add about 1.5 gallons to the tank (how much it needs to be at the correct water level).

How about you guys?
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