I have 3 self watering containers? Each is 3ftx2ft and approx 1 ft deep. Would i be able to grow a cucumber in 1 a zucchini in 1 and a bell pepper in 1? I got these containers at a garage sale, and they dont show when they are full of water even with the thing you fill the water in? So how do i tell if they are full then? They are from natural gardening catalog, Their newer models of different planters have a gauge that tells you when its full and when they need water.