I have 2 fantail goldfish in a 3.5 gal tank on my kitchen counter by the window. While not as interactive and fun as my Bennie, I do enjoy them! I also take care of a 55 gallon tank in the nature center. Children especially seem drawn to the movement and color. I have black skirt tetras, black and dalmation mollies, red platys and an albino plecostomus ("sucker fish"). I think it's cute how they all come to the front and top when I come over - I know they're just expecting to be fed, but it's still cute!