I'm thinking about getting a pair of scarlet badis for my 6 gallon planted cube. My fish store currently has 2. One of them is very obviously a male but I'm not sure about this one.
You may be right, although all my females (and there's been a lot) are always gray. They sometimes display shades of gray stripes and rarely display hints of color and never any permanent red coloration.If that is an adult fish it is very likely a female - females are grey or just a touch of colour while males are quite brilliant: