Adorable, on a side note tho don't keep the gravel in there too long, they will eat gravel and it will impact their intestines and kill em. With RES and stuff just try to make sure it can't fit in their mouth. however you can go with sand and if they eat it they will just poo it right out with no problems. A bag of play sand should do the trick. I have 3 in my pond and I like the look however if you get sand make sure you rinse it really really good. I thought I had but I did it all wrong and ended up with a murky pond for a week had to do plenty of 50% wc, filter emptying and cleaning and waiting for it to clear up