No offense, but I would never take recommendations from Super Pets. I have been there twice I will never go back. Both times I counted half a dozen dead fish just sitting in there tanks, and many of there tanks were over run with pests like aptasia. The store is all about their bottom line, and cares nothing for the wellbeing of the livestock they carry. I've heard this same complaint over and over about that store. I hope it doesn't appear I'm being rude to you, I'm just trying to warn you before you start wasting your money there. They don't quarantine their fish before they start selling them to the public, so you could get a fish that just spent the last 24hrs in a cardboard box. All 3 stores I list below hold onto their fish at least a week before they sell them to the public, and this lowers the risk of you buying an unhealthy fish that will die on you when you take it home. There are two great stores over on your side of the beltway. I would check out:
http://www.blueribbonkoi.com/
and
http://finsandfeathers.storesecured.com/
Both stores are run by hobbyists and take great care of their livestock.
If you want to travel to the MD side of the beltway, you can also checkout:
http://www.scales-tfw.com/
Best of luck with whatever path you take.