Yeah there are a few very similar that get to about 20 inch and above and true i mean I'd be eventually getting a bigger tank but I didn't know about the offspring being possibly different size ill look into that thank youI looked into this a few years ago. If I remember correctly there are a few larger rays that look very close to the "teacup" rays and are sold as those. You have to be sure the seller is/has the correct info. Same goes with the "dwarf" rays just because both parents are "dwarf" doesn't mean their offspring will be also.