@HashGirl
Thanks for your question. I'll try to clear some things up.
The picture you grabbed doesn't have the SIP bucket in the picture. It is out of the tent waiting on a new 'renter."
Although, the bucket overflow saucer (brown) is in the center.
Other Resident in the Tent:
The other 4 pots you are looking at are AutoPots XLs with 5-gallon fabric pots. Those are fed from a 12-gallon reservoir sitting outside the tent. That's why the floor is covered in nutrient-delivering tubing.
Food for the Ladies:
That outside rez is loaded up with all the "clear-ish" nutrients and supplements. I say clear-ish because Mr. Fulvic is pretty black, but so little is used that it doesn't "funk" up the rez or lines.
Back to SIP Buckets:
If you were referring to an older picture that has a yellow bucket, that is the only actual SIP bucket currently waiting for action. I have a short plant stand that I put under it to keep the bucket up off the floor and away from the tubing.
Below, I've attached the older picture that featured the SIP.
More on GroBuckets:
My particular version is called the "GroBucket." I'll include a pic of the guts of that setup.
This time I went with a 3.5-gallon bucket, instead of 5 gallons. I did that to keep the levels of each pot at a similar height for grow-light coverage. The idea worked pretty well. The bucket's soil level is only a couple of inches above the other pots.
Regarding nutrients for the bucket, my plan is to dip into the large reservoir for the AutoPots and feed the exact same thing to all the plants.
My "Expected" Setup (if I can germinate a healthy seedling) to make 5 plants:
GroBucket Internals:
So, does the container in the middle hold the water/feed for the 4 plants around it? If yes, is it really a SIP if there is no water or air gap in the bottom of each pot?