A fully recirculating system for seedlings: yet another use of the To Go Cup Thing

Honest folks I don't sit up thinking about this. I simply had a need and had a solution. The need is one that recirculation answers: keeping new and developing root systems rich with nutrients to get the most out of your (my) setup. I discovered long ago how keeping a constant stream of nutrients flowing over the entire length of the root system made a difference in growth and vitality but could never make it work with my (then) current grow setup. Many grows later my grow mentor asked me about it which caused me to dig thru the pics and ideas I had and realized I could implement some of them now. The first was simply providing recirculation for plants that were vegging and preparing to finish outdoors. Then I had the situation where I had 5 more autos that had JUST sprang from seeds in the seed starter, gave them some more time to develop at least a single pair of "real" leaves and then wanted to move them to my managed environment.

I also knew I wanted to do recirculation to give these tender young things the best chance possible while coming up with a nice, re-usable process and guess what, the to go cup comes to the rescue again! The only modification I made to the cup itself was I took 6 "units" or cups modified to by my grow cups with lids that snap on the top. Recall these used to be soup to-go cups for restaurants. Well, I took the lids, hacked a nice 2-inch square hole in the middle for the plant, then I drilled a hole on one side just inside the lid lip.  Follow the pictures to see why.

What I built:
1. Start with cup, right-side up:

2. Insert a common netcup, think its two inches, maybe three, have so many lying about:
3. Add a little hydroton to bottom:
4. Get a just-sprouted autoflower from the deep water culture rig I use for cloning and other things:
5. Transplant by just setting smaller netcup in bigger one on top of the hydroton and fill in around it to bury it well (not the leaves but everything else):

6. Add my modified lid (see above):
7.  Add the little rig I made that will keep the feed line in place while forcing the nutrients right down the middle of the root system. I use a modified plant label as a further tube holder/bracer. After working with this I will probably retool this
removing the stiffer brown tube with ultra-flexible black tube.

Close up of the feed line. Normally pointing down.

8. Do that for the rest of the new sprouts:

9. Finally, add a 30 gal per hour pump to the tub and run the tube from plant to plant. Voila! All plants managed plus constantly getting nutrients forced over the root system. I will leave these in place to later document what a difference this can make.




  1. Hey Jeff, I don’t quite get it and can’t tell from the pics. Are you running the tubes into the hole you drilled near the top, placing the Tee, then putting a “tail” on the end of the Tee which you’re sticking through the hole in the little while holder thing you’ve made. And I take it you’re leaving that tail open and turned upwards to allow gravity to stop the flow on that end.

    I’m assuming you’re initially bringthe tubing in through the hole in the lid you made and running it beneath the lid and coming out the central 2” hole in the lid where the Tee and tail are placed to exit the lid at thiat point.

    If I’m wrong, please correct me. Also, are you just allowing free flow or placing an emitter on the Tee?


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