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Derbybud's automatic watering system: A tutorial


Member of the Year: 2018 - Member of the Month: Jan 2018, Nov 2018 - Grow Journal of the Month: Aug 2018 - Plant of the Month: Oct 2018
Greetings all! Here is a tutorial on how @Derbybud made his auto watering system. This is the basic information that folks are often asking him for...no reason he needs to keep repeating it. He's a busy guy :). These are his words:


My rez is just a 27 gallon black tote.

Pump is min of 300 gal/ hr. Pump in tote into tent thru 3/4 or 1" pvc.

In the tent I have a 4 way head that I got from Lowe's in the lawn watering area. From there I have individual shut offs with equal length 1/4" tubing to my pots. Equal lengths is key or some pots would get more than others and if i need that I close the shut off some.

At the pots I have halos that i made from 1/4" tubing. For the halos I just drilled 6 holes and with some wire they hang off my cages. I have a better second timer but always just program to the min. I run the pump anywhere from 2-4 min depending on how much run off and how light they are and kinda watch what the plants need.

This picture is the whole set up other than the halos that go around the plant. I have too many disconnects as you should only need 2. One in the rez and one in the tent.

As far as pumps, I just get them from Harbor Freight. The one I've been using since setting up my first one was just 380 gallon/ hr. It was made for a sure drip system. I do have a new one in my second waterer that is 640 gal/ hr. I might need to use the seconds on my timer but I will probably just crack the one shut off a little more to circulate more in the rez. Most I paid for a pump is $38 for the 640.

To mix nutes, I usually mix at least 10 gal. I close the blue shut off and open the red one and override the pump to turn it on. This pumps the mixed nutes to the far side of the rez and acts as a shower with the holes that are drilled in the end cap of the pvc and with the pump on the other side of the rez things get good and mixed (see mixing below).

Here are a couple of the timers I use:

I start with putting 7 1/2 gallons in and my pump mixes the rain water with the last of my mixed nutes. Then I add my silica and let that mix for 15-20 min. Then I add my cal- mag and other nutes. Last I add my Z7 and orca (liquid great white). While that mixes in I take my last 2 1/2 gallons and clean everything up and then dump it into the rez. After a few minutes I check ph and adjust. Once all looks good I turn the pump off and put it back on its schedule to feed the girls. Once timer is set correctly, I open the blue shut off and close the red one almost all the way. I leave it cracked so when the pump comes on to feed it also stirs up the rez a bit. I have at least 1 but usually 2 air stones in the bottom running 24/7. I have my rez on some pieces on wood to angle my mixture toward the front right of it where my pump is. I don't run a filter like some due and I've never had issues as I only use liquid nutes.

The pipe with the holes that hangs over the the rez (supported by the wire in the pic above) is for mixing nutes. Close the shut off to the tent and open the one in the rez. Override timer and turn pump on. Add water and nutes and the pump with the shower head on the opposite end mixes things really well. Once nutes are mixed and ph is adjusted turn pump off and set back on timer mode and open shut off to tent and close the one in the rez. With my bigger pump I'm leaving the shut off cracked some and when the pump kicks on to feed the plants thru my halos it also stirs the rez a bit.

Biggest thing with me is keeping run off to a minimum and making sure my coco stays moist enough so i don't get hot spots. That's why it's best to do more small feedings as it stays moist with minimal run off. Keeping run off to a minimum keeps the rh lower and slimies from growing in my drip table till I get back. If I'm home i might add Z7 every 3-5 days but I've gone 16 days without a problem.

Just think simple on what you want to achieve. Don't over think it. Move a certain amount of water for a certain length of time. Done. The magic is in having all feed tubes the same length to get close to the same amount of water. When I set things up I turn on my pump with my 1/4 hose ends in 2 liter pop bottles to see how much flow I'm getting in a minute. Then I can see how much I want to feed. If in my minute I get a liter and I want to feed 3 liters per feed I have my timer run 3 min per feeding. After a few days of checking how much run off or how light the pots are I change my timer settings on more or less time to run the pump. Towards the end when they don't drink as much I just set the timer for less time to run the pump while watching how much run off.

Note that in flower, I feed 3-4 times a day and never at lights off. So lights on at 6:00 am so feeding happens at 6:30, 10:30, & 2:30 with lights off at 6:00 pm.

If you're in hempy it should be easy pasy, as long as they're eating about the same. Just make a manifold out of pvc, and make sure your fingers are the same length going to the pots.

This is the system in the tent:

Cleaning the rez is easy too. Close valves, unplug pump and air stones, take pvc apart at union in the rez, slide rez over union, dump what's left in yard, clean pump in sink, clean rez in shower, done. If you look closely you can see that the 90 pvc on top of the pump is not glued so i can break it apart easy to help with cleaning. If it leaks some it's in the rez.

Hope this helps some! Now questions...
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