Mile High Koi was an independent specialty fish shop based in Englewood, Colorado, serving local customers with koi and goldfish. The business offered live fish alongside nonliving pond or fish-related products, and its website also featured adoption and rehoming information. Run by an owner who described himself as a fish enthusiast, the shop took an unconventional, personal approach to keeping and selling fish. Customers could contact the business by phone or email and arrange appointments to view available stock.

Mile High Koi announced that it was closing, with the business officially closed on September 24, 2026. Before closing, the owner sold the remaining goldfish stock, including shubunkins and larger goldfish, and said there would be no koi for sale in 2026. The owner also stopped accepting new fish and rescues. The shop thanked customers for their support over six years and shared updates through its blog and Instagram. Its former address was 3298 S Sherman Street, Englewood, Colorado.