Walmart offers the the Hawkeye 2-Gallon 360 Starter Aquarium Kit with LED Lighting, model no. AQV360H2, for $22. Opt for in-store pickup to avoid the $4.97 shipping charge. That's the lowest price we could find for such an aquarium by $7, although we saw it for $2 less in March. It features an under-gravel filter and air pump.