Root tabs placement in a 20 gallon tank

[Quan]

Good morning,

I have a quick question on how to plant the easy root tabs. Per the instructions "Insert 1 capsule every 4 to 6 inches in a grid-like pattern". I'm still confused about this as English is not my first language. Does it mean place the first tab 4 inches from every direction and then place the next tab 4 inches away from the first tab? I have a 25x13 tank, could anyone tell me how many tabs do I need to place to get the maximum benefit?. I'm a total newbie when it comes to planted tank.

Thank you so much for your advices.

[Maggie]

I just put mine under the plants that use them. But if you want to fertilize the entire substrate, think of the bottom of your tank like a chess board with squares. Each square is 4-6" in length and width. Now place one tab in the middle of each square. Hope this helps!