DWC water level for seedlings.

Hi all, Just wondering if I'm on the right track, first time with DWC, was compost previously.

I have this: https://www.hydrohobby.co.uk/dwc-oxypot-4-kit.html

I think I will transfer the seedlings, still in root riot cubes into the baskets of clay pebbles, once the roots breach the cubes.

I did a dry run (wet run?) with the water level a tiny bit below the bottoms of the baskets, after an hour or so, I could feel all the pebbles were slightly damp, right up to the top pebbles...

But not wet, or dripping, so I figured this would be enough moisture to keep the seedling happy and it's cube damp enough whist encoraging it to put roots down?


Do I have the right idea here?

Thanks

futurebanjo said:

Do I have the right idea here?

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Yes

Have fun

Yep, thats the idea.. Drop the level as the roots grow..

Thanks, yes,

I figured once the roots hit the water properly, I'll lower the water level in the tank, ec/ph permitting. I'm just a bit worried about the transfer phase, as growing in dirt before, I just plonk the seedlings striaght into the compost.

Does it work if nutrient solution is thrown on the top of the pebbles like watering a pot?

Younger777 said:

Does it work if nutrient solution is thrown on the top of the pebbles like watering a pot?

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Yeah if no roots showing yet yes top feed them

One more question(s) if you don't mind,

'Yeah if no roots showing yet yes top feed them'

Do you mean no roots showing out of the basket or the root riot cube?
I plan to water them with a starter nute at very low EC whilst they are still in a make-shift propagator, but i'll still have a load of starter nute solution left, probably enough at a guess to get the tank up to the correct EC/PH.

Should I quit using the Starter nutes at this point, transplant and use the A/B veg nutes for the main tank? I guess it doesn't make a huge differnce.

BUT, sorry one more question, I've read a lot about replacing all the water/nute solution in DWC, some say evey two weeks, some say just when you flip to flower, etc.

That aside, do I need to drain every last drop out of the tank? or can it just be diluted with solution that is pre balanced with PH/EC nutes?
Basically, do the unused nutes settle to the bottom causing a concentrated mixure of 'stuff' that might be detrimental?

These might sound like strange questions but I don't have a seperate res, my resevoir is literly a 125L bucket that a few plants will be sat in, all the time, so it's one of the only things I'm not really understanding yet.

Yeah if roots not showing out of net pot. Nute strength depends on your plant's. I'd use that weaker stuff till they are good and established in the new system at least. I go off my plants as far as rez changes go. Especially with a 33 gallon rez. It will problem be pretty easy to maintain

I only change res once throughout entire grow...as you say, when I change to flowering nutes. Works for me. I've never had a problem.

I also don't use any nutes at all for the first 5-7 or so days. But I generally run lower ppms than a lot of people I see on here.

And nothing should settle out in your res. You should have constant mixing from the airstone.

And yeah you want to get it all out when doing a res change. Not literally every single drop, like the stuff that sticks to the walls etc, but yknow...you dont have to wipe it down or anything. Like if it was a small bucket I'd say invert it to tip it out and then immediatley flip it straight back up and refill.

As you get a grow or two you'll learn to read your rez along with plants. Its is its own ecosystem and I don't like to disrupt it if it is running good. If it don't smell and you have what looks like good clean water (slightly tinted from nutes possibly) and ph is good I roll with it.

Thanks,

The starter nute is one part liquid 1.9 /1.1/2

Veg A is 3.5/0/0
Veg B is 1.8/2/5.2

All from the same brand so will hopefully work together, just wondering if I should have bothered with the 'start' nutes and just used really weak veg nutes.

When I started out I would water my seedlings manually until roots hit the res. I've since found that they grow more lateral roots if I don't water them manually. The moisture in the bucket is enough to keep the hydroton wet, and that's plenty for the seedlings.

LKABudMan said:

When I started out I would water my seedlings manually until roots hit the res. I've since found that they grow more lateral roots if I don't water them manually. The moisture in the bucket is enough to keep the hydroton wet, and that's plenty for the seedlings.

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Thanks, yes, that makes sense...

I did a 'dry run' with water level just under the bottom of the net pots, and after a few hours all the clay pebbles were moist/very slightly damp but not wet or dripping if you know what I mean.

So my current plan is to not top feed at all, I plan to germ the seeds in a makeshift prop, using 'root riot' cubes' which don't have any fert in them. and put the cubes straight into the clay pebbles, unless I can trim a bit off without cutting any roots.

Previously I've just germinated in a tape cassette box with some damp tissue paper in it, so this is all very high tech to me

I'll post a grow log soon once I get going, I think I'm almost there, in terms of preperation. hahaha! famous last words!

I use the EZ-Gro plugs, like the root riot ones. Don't worry about trimming anything off, just put the plug in a layer or two of hydroton and then fill in the sides. Good luck!

futurebanjo said:

Thanks, yes, that makes sense...

I did a 'dry run' with water level just under the bottom of the net pots, and after a few hours all the clay pebbles were moist/very slightly damp but not wet or dripping if you know what I mean.

So my current plan is to not top feed at all, I plan to germ the seeds in a makeshift prop, using 'root riot' cubes' which don't have any fert in them. and put the cubes straight into the clay pebbles, unless I can trim a bit off without cutting any roots.

Previously I've just germinated in a tape cassette box with some damp tissue paper in it, so this is all very high tech to me

I'll post a grow log soon once I get going, I think I'm almost there, in terms of preperation. hahaha! famous last words!

Click to expand...

Yeah that's the way, you get your water level just right and the popping bubbles will keep the hydroton moist. Like you said not dripping but just right.

Just germinate in paper towels on a plate in the dark. Easy

trippsy25 said:

I only change res once throughout entire grow...as you say, when I change to flowering nutes. Works for me. I've never had a problem.

I also don't use any nutes at all for the first 5-7 or so days. But I generally run lower ppms than a lot of people I see on here.

And nothing should settle out in your res. You should have constant mixing from the airstone.

And yeah you want to get it all out when doing a res change. Not literally every single drop, like the stuff that sticks to the walls etc, but yknow...you dont have to wipe it down or anything. Like if it was a small bucket I'd say invert it to tip it out and then immediatley flip it straight back up and refill.

Click to expand...

Interesting - only change the res when going into flower. I've changed weekly or bi-weekly for my past (three) grows so I'm interested in how more experienced growers deal with res changes.

What size res are you using and how do you "top off" when the nutrient solution is taken up by the plants?


OP - don't intend to hijack the thread - you'll be dealing with this issue RSN.

Oh, yeh, I replaced my air stones with Bubble Mac #1020TP and they absolutely rock. Same pump but lots more aeration. Not cheap but worth a look, at least.

Yep. If it aint broken, don't try to fix it. Over the few years I've been growing dcw, on only two of my twelve-ish grows did I need to do any other res changes. Something went wrong those two times. What? I dont know, but it resulted in the chemistry going out of whack so a res change it was which corrected it. Otherwise yeah I usually just change once about 2 weeks into 12/12 when I start using flowering nutes.

I usually grow in 20L tubs, one plant per tub. This time round I've got one large reservoir...100L with 4 plants in it. The plants drink about 4L every day so I just take two 2L bottles and fill em at the tap and pour it in the res. Then test PPM and add nutes to bring it back up after the slight dilution. Then test ph and usually add a few drops of ph down. Done.

Cool thanks, My water is ph 7.5 so I got some PH down, 81% phosphoric acid, I guess i'll need a bit of that even after adding nutes - thing is how much do I need to add to adjust slowly without overshooting? tank will be about 100L of water. 5ml at a time? or is that going to fast?

futurebanjo said:

Cool thanks, My water is ph 7.5 so I got some PH down, 81% phosphoric acid, I guess i'll need a bit of that even after adding nutes - thing is how much do I need to add to adjust slowly without overshooting? tank will be about 100L of water. 5ml at a time? or is that going to fast?

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I use the Advanced Nutrients pH down, which is pretty strong. For my 45g / 170l res, 2-3ml will make a noticeable difference. Go slow and stir between each addition. And remember that your nutes will probably lower the pH some as well.