Walmart offers the Hawkeye 5-Gallon Aquarium Kit
, model no. AQ15002, for $20
for shipping. (Free Site-to-Store pickup is also available.) That's the lowest total price we could find by $7, although we saw it for $2 less a week ago. Sales tax is added where applicable. The kit features a 5-gallon acrylic tank, fluorescent hood, power filter, and more.