I build a lot of acrylic products for my customers, and take pride in my work. This is dosing reservoir that was recently ordered, and it came out really nicely. Each zone holds 1g of solution, such as Alkalinity + Calcium + Magnesium + Acropower perhaps. Dimensions are as follows: 21.25" long x 5" deep x 12" tall. I used a blue base for a nice look that matches the custom Sump and Top Off Reservoir the buyer ordered.