Ebb and Flow Flood Level

[Xare]

My local hydro shop has 3'x3' ebb and flow trays, some are 4 inches high and some are 7"

4 inches seem a bit low... I will be using 7 inch or 8 inch square pots with clay pellets for a SOG hydro. So the 4" tray at maximum would only flood about 1/2way.

What is the optimal flood level for ebb and flow for SOG ? about half way or as much as you can ?


Looking at the fittings for the flood and drain system I see they have extensions so you can adjust the fill level.


I could get the 7" tray with 7" pots and fill up to 6" if that is best.

 

[potroast]

Yes, do that.


You will want the extra depth for sure. You will probably flood to 4 or 5 inches, but that will be determined by where in the pots your starter cube sits. Flood to just below that level, so the cube does not get soaked.

HTH

 

[slek]

So in my hydro trays they are going to have 8" walls, where I will have a 36" rockwool slab with the cube holding the clones sitting right above that. I was going to put airstones in the bottom of the trays and find a way to prop up the rockwool a bit so later the roots can just chill in the solution down there (a gap with no medium would be present). Is this a bad idea though? I should let the trays fill up to about 6-7" and let the solution sit there? Or should I just let it stay filled that high for a certain amount of time? Was gunna use drip stakes and planned on running them for 3x a day for like 10-15 mins.

 

[VictorVIcious]

So in my hydro trays they are going to have 8" walls, where I will have a 36" rockwool slab with the cube holding the clones sitting right above that. I was going to put airstones in the bottom of the trays and find a way to prop up the rockwool a bit so later the roots can just chill in the solution down there (a gap with no medium would be present). Is this a bad idea though? I should let the trays fill up to about 6-7" and let the solution sit there? Or should I just let it stay filled that high for a certain amount of time? Was gunna use drip stakes and planned on running them for 3x a day for like 10-15 mins.

Dude, they answer is MEDIUM DEPENDANT. Potraost has a Thread were he explains the best watering method depending on the medium your using. The rock wool slab would be maybe once a day at most, and you would water the block sitting on the slab for the first few days until the roots get down into the slab, after that just the slab.
If you want to do aero, do aero, forget the rockwool slab and the drip system and the rockwool blocks. Rockwool retains more water than any other medium, you would water it once a day, drain any excess away so your plants don't drown. VV

 

[Eharmony420]

So in my hydro trays they are going to have 8" walls, where I will have a 36" rockwool slab with the cube holding the clones sitting right above that. I was going to put airstones in the bottom of the trays and find a way to prop up the rockwool a bit so later the roots can just chill in the solution down there (a gap with no medium would be present). Is this a bad idea though? I should let the trays fill up to about 6-7" and let the solution sit there? Or should I just let it stay filled that high for a certain amount of time? Was gunna use drip stakes and planned on running them for 3x a day for like 10-15 mins.

Lol, I literaly cringed when I read this. I use 4 in rw cubes and mini cubes. Ow. Read. Al b fuct and grodan are also good resources.

I got this off bg hydros website. In Rw blocks in turbogarden pots i flood 2 inchs for 2 minutes.

This will tell you how many gallons to flood the table with in order to the reach the height you want. For example I use 11 gallons to flood 2-3 inchs up. The calculation for this is quite simple: Height you wish to flood in the tray (H) x Width of the tray (W) x Length of the tray (L). For this calculation it is best to convert feet into inches. Then multiply the cubic inches by 0.0043 to convert it into gallons.

 

[marchold]

Dude, they answer is MEDIUM DEPENDANT. Potraost has a Thread were he explains the best watering method depending on the medium your using.

I am using coco in gallon water jugs, I have a 7" tall flood table which means a lot of the coco never gets wet. This seems to control the gnats as and my plants look great. I think only the bottom 50% of my pots have a lot of roots in them. I was thinking of using 50/50 coco and vermiculite in the top so it would wick the top half.

 

[VictorVIcious]

I am using coco in gallon water jugs, I have a 7" tall flood table which means a lot of the coco never gets wet. This seems to control the gnats as and my plants look great. I think only the bottom 50% of my pots have a lot of roots in them. I was thinking of using 50/50 coco and vermiculite in the top so it would wick the top half.

The only medium that holds more water than coco is rockwool. The same watering rules would apply. I use 3" rockwool blocks into coco coir in pots a little a taller than 6 ", I make sure that I do not let the water hit the bottom of the cube. When it rains, the rain soaks into the ground quickly, it doesn't stay around the top very long, and not much is right around the stem, the leaves shield it away from it. The rest of the time the roots deeper in the soil, or the bottom of your pot, feed the water up to the tap root and then into the plant, Its this little root hairs that are small enough to take up molecules that feed your plant, not those big honkers at the top. VV

 

[slek]

Well Im sorry guys, I have never done a hydro grow and am pretty ignorant on alot of subjects. But thank you all for the help anyways! And sorry Xare I did NOT mean to hijack your post, but it seemed like your questions had been answered and mine are on topic. Right now I am just finishing a white widow (omg they have taken forever) soil grow, and already have the rockwool slabs and cubes for the hydro grow next.

So name of the game for me will be to flood my channels about once a day, wait for the channels to get full, and then unstop them sending anything non-absorbed by the rockwool back to the res via gravity. Rockwool should stay moist enough throughout the day to keep the plants fed apparently, even though im from a really dry region.

Also, for the res solution, does it matter what kind of water I get? I REALLY dont want to use my local tapwater, due to it being extremely hard water and high in sodium based things (like high enough to make permanent stains in the showers and form salt rings in evaporation trays). So I was contemplating on buying my H20 from the store...

 

[VictorVIcious]

Well Im sorry guys, I have never done a hydro grow and am pretty ignorant on alot of subjects. But thank you all for the help anyways! And sorry Xare I did NOT mean to hijack your post, but it seemed like your questions had been answered and mine are on topic. Right now I am just finishing a white widow (omg they have taken forever) soil grow, and already have the rockwool slabs and cubes for the hydro grow next.

Hey welcome to the discussion and since it is about flood levels you are not hijacking, your adding to the discussion. Yes, I had some widows that flower for about 14 weeks, they are shown in my avatar.

So name of the game for me will be to flood my channels about once a day, wait for the channels to get full, and then unstop them sending anything non-absorbed by the rockwool back to the res via gravity. Rockwool should stay moist enough throughout the day to keep the plants fed apparently, even though im from a really dry region.

I am not sure you understand flood and drain, matter of fact I am sure you don't. You don't have to unstop anything in a flood and drain system, when the pump shuts off the water will simple drain back into your reservoir thru the pump because it will drain by gravity.
What you want to do is get a timer, plug your pump into it, lay your ph'd rockwool slab in it and turn your pump on, time how long it take to flood the tray about three inches deep, set your timer to come on for that amount of time once a day, I set mine for two hours after lights on, and then just monitor it.

Also, for the res solution, does it matter what kind of water I get? I REALLY dont want to use my local tapwater, due to it being extremely hard water and high in sodium based things (like high enough to make permanent stains in the showers and form salt rings in evaporation trays). So I was contemplating on buying my H20 from the store...

It sure does, 90% of the plants is water. IF your water quality is that bad, and you are going to go hydro you might want to consider on ro system. I bought mine for about $200.00, spend $120 a year on replacement filters, I have five 30 gallon reses to change every two weeks, it does fine. Until then it might be helpful to just let any water you use sit for a day before using it, always ph after you add your nutes, the nutes have buffers in them and will affect the ph.

 

[slek]

Sweet, that answers all my questions for right now, thanks alot on the help Victor. +rep