Walmart offers the Tetra 1.5-Gallon Aquarium Cube Tank, model no. 29133, for $19.98. Opt for in-store pickup to avoid the $5.97 shipping charge. That's a buck under last month's mention and the lowest price we've seen. (It's the lowest price now for such a tank by $3.) It features a 9-LED light and integrated drawer for aquarium supplies.