I have put together a small tray unit with things I had around the house to try ebb and flow out. If It works well for me, I will probably make a larger one. I used a tray that is 18" x 18" x 6", a 10 gallon tote, Botanicare ebb and flow fittings, and a 160 gph water pump. This unit will go into a 32" x 32" x 60" tent that I have. I will be running 2 150W HPS and a 110W T5.

For this first run, I want to use 4 Satori clones that are still fairly small. They are in 3" net pots in DWC right now. I plan on just putting the 3" pots into the tray and then fill the rest of the tray with hydrotron. I do not have a timer that I can set for less than 15 minutes and cannot afford to get one now.

So my questions....How many times a day should I flood the tray? How high do I want the water to get before it starts draining out? I can make the overflow any height I need with a PVC threaded coupling and a threaded nipple. I also have some concern that the hydrotron and plants will float around if I get too much water in the tray. Is there any benefit to adding an air stone to the res? I know that the water draining back into the res creates some air bubbles, but is it enough to keep the nute solution from going icky?

That is all I can think of right now, but I am sure that I will have more questions when I get this actually going. I need more clay pellets which should be here tomorrow. So hopefully, I can get this up and running Fri or Sat.

Hi Hemp Goddess,

not a lot of help here, but I wanted to let you know that I also needed a Timer that would run for 'small' increments of time, like 1 minute ...
I bought the Apollo 9 dual digital timer for 16.95 and it works excellent.

I promise you I have no affiliation with this company and this isn't spam or ham . . .



I see no reason why using a timer like this wouldn't work great for you and it's less than seventeen bucks!

Just thought that maybe you had overlooked this option.

I wish you good luck on this ebb and flow experiment!

Being a huge fan of Mandala Satori, I can't wait to hear how they turn out.

peace

Found this THG,,hope it helps

Hydroton:
Hydroton is expanded clay and during shipping some sediment will occur, always be sure to rinse away this sediment with fresh water, essentially “cleaning” the rock before you use it. When flooding with hydroton I have to bring the water level up almost as high as the container I am using, most importantly I am looking to make sure that the roots are getting saturated. The water level has to be higher than rockwool because hydroton doesn’t have the same wicking capabilities. Also, I always start off with a once a day flood for 15 min at a time. By the end of week 2 I am able to bump up the watering schedule to twice a day. As the plants grow and I get close to flower I move to 3 times a day, still for 15 minutes each time. Remember, this all depends on the size of the containers used for the plants. I start in 6-8″ baskets and flower in 2-3 gal pots. If I kept the plants in the 6-8″ pots I would probably end up watering more often

Also this

http://www.cannabis.info/USA/library/719...rain-technique/

Quote: The Hemp Goddess wrote in post #1

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So my questions....How many times a day should I flood the tray?
To start I would go once a day. A good test would be to water and see how long it takes before the plant starts to go limp and take that time and divide by half. As the plants get larger they will go to twice a day normally around the time they go in to flower.


How high do I want the water to get before it starts draining out?
Only at about half way up depending on total depth of the medium. May be tough to do in a homemade setup filled with medium. I'd suggest using larger netpots and then flood about half way up the pot. You never want the water to reach the base of the plant, but a little moisture is ok.

Is there any benefit to adding an air stone to the res?
No, and in fact it will cause the system to grow algae at a more rapid rate in a small system. Not so much on large systems but flooming is always going to be better.

I know that the water draining back into the res creates some air bubbles, but is it enough to keep the nute solution from going icky?
Darkness in the rez will always be key. With out light algae can not grow, and so long as you change your rez fairly frequently [every 2 weeks with water tops offs daily] nutes should be pretty clean except for some clay pebble dust that forms on the bottom.

That is all I can think of right now, but I am sure that I will have more questions when I get this actually going. I need more clay pellets which should be here tomorrow. So hopefully, I can get this up and running Fri or Sat.

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THG if you keep the hydroton higher than the water level the hydroton won't float as easily. Air stone in the res ,I say yes because the water is not continuously recirculated.

Thanks everyone. Weatherman, I will check out those timers. Weedhopper, that helps a lot. PJ, I will check out the rockwool croutons. If I build a larger unit, I will need more medium. I know I will have more questions. MR1--I kind of was thinking the same. At any rate, it won't hurt anything and I do have an air pump lying around that I can use.

I love trying new things, but it is great not to have to "reinvent the wheel". I appreciate all ideas and suggestions.