You can use the 100W CHE as long as your light fixture/dimmer or on line thermostat is rated for it.
Watching an African Bullfrog growing is fun and can bond you to it. It really does not matter if it turns out female or even not a giant species. Mine is full grown 4 in. male with both Giant and Dwarf traits. Fits in a 29G fine and feeding it night crawlers does not break the bank. Behavior wise it's all GABF and attacks the cleaning gear or tongs while I service tank or feed it.
If purchasing baby GABF recommend LLL Reptile since from feedback it pretty much guarantees you will get a GABF. Also; if you want a male and get a female; it's easy to sell/trade those as adults and you can get another baby and try again

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