I had to search for their usage instructions on-line and when they say "1/4c per 5 gal potting medium", I think they mean at the time of planting when it can be fully incorporated into the mix. Otherwise, it says "1 c per 10 sq ft growing area or 3 c per 50 feet of row", which I would use for roughing up a calculation. What is the growing surface area of each tank? (width x length). I'd start out with a lesser amount too simply due to the rounded tank shape holding less medium.

ETA: I suspect your use of 1.5 to 2 c per tank was about twice the amount they recommend, but maybe your tanks are larger than I imagine.

Hi party_music. Thanks for helping me. I have trouble reading, but I should have looked it up online instead of just the package.....but maybe I missed it there too.

I sort of freaked out when I thought I may have added to much, since I used it on all the tanks with tomatoes. Okay........so these tanks are oval......and are around 6'6" long and 2'5" wide and around 16" deep. So not counting the depth, it would be about a square footage of 16.25. I'm thinking I'm okay. My brain is spinning. It's sort of weird doing square footage when you take depth into account. Sorry if I sound a bit challenged. So knowing this info now.......does it sound like I didn't over-do it?

Thanks!

It is pretty darn hard to overdo an organic fert like Dr. Earth. By nature slow release, it will continue to feed your tomatoes for much of the rest of the season without need for reapplication.

It's all good :-)

Thanks, gardengal!