Used correctly Metro is effective against many internal parasites. Used incorrectly (overdosing either in quantity or treatment duration) it can mess up the animal's liver and kidneys. What makes you think your frog has a protozoan/bacterial problem now? If it's stressed so much about the present environment, maybe the solution is to return it to it's normal set-up. I get the Plantation Soil 8 QT bricks at less than $7 for the 3x pack. That's a lot of shredded coco should you need to replace it sooner than monthly. Good luck

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