Need help on specific DWC question

[Marley Man]

Hey everyone. I recently posted at another forum about what the water level should be when the rockwool seedling has just been placed in the netpots with hydroton.

The advice I got was to have the water level 1 cm away from the rockwool. This means having part of the netpot in the water too.

I am cautious to do this, because when the water is at the level of just below the netpots, the roof is splashed, so why wouldnt the rockwool be splashed? the hydroton retains water doesnt it?

Would really appreciate some advice on what to do

 

[Medical Cannabis]

Hydroton doesn't retain water. That should be about right. Its okay to have the rockwool get wet. It should be if they're seedlings.

 

[Marley Man]

Thanks very much WCT

now that that is solved, I had a question about nutrients. The seedlings are just starting to have their third set of leaves. Is it a good time to add nutrients, was thinking of adding just 1/16th strength. Just bought a tds meter but its shipping from hong kong so no idea how long that will take.

are also using tap water and don't know how much ppms that is but it was let to sit out for more than 24 hours.

 

[Marley Man]

Well 4 plants were put into the netpots. The ph was adjusted to 5.5. Half a day later the ph was back up to 7.0 so it was readjusted back down to 5.5.
3 of the 4 were very droopy and weak. The next morning, the 3 were completely dead. Its heartbreaking to see it, It kills me that I did a lot of research to do all the right steps, and I believe I did do all the right steps, but somehow they are killed. There are no signs of ph burning, the leaves were all quite green. the roots had even grown at least an inch out of the rockwool cubes.

There is one remaining. I dont understand how 3 could be killed so easily and one be unaffected. Any ideas on how to keep it alive. I plan on moving it to a 5 gallon bucket system and to use distilled water with a weak amount of nutrients.

 

[Boss]

5.5 seems low to me.

 

[Racefan]

5.5 is really way too low. 5.5 is the PH you PRE TREAT the rock wool with to get it ready for planting. NOT the actual PH you use for growing.

 

[Marley Man]

Most of what I have read said hydro ph should be between 5.5 and 6 including this site: What pH Level or Range Should I aim For?

 

[Racefan]

Well then maybe someone else here with extensive hydro experience should address your problem since you obviously believe what you've read in the past over what I just wrote. Your having problems and I've given you the correct answers. Do what you want but what ever it is...make a change because what your doing is flat out killing them. (that alone should tell you what you read wasn't 100% right) 5.8 to 6.2 is the average most use. PH is extremely important. Any .1 in your meter reading difference is a huge (10X's) difference and needs to be addressed ASAP.

Good luck.

 

[Marley Man]

I wasn't trying to say you are wrong. But when I see two conflicting pieces of information, it doesn't make sense. Wouldnt you also be confused if the guide you are reading from the forum says one thing when it really should be other?

If I came of as hostile it wasn't my intention. I was commenting with the approach that there is reasoning behind each answer, I was just trying to figure out that reasoning. Thank you for your help it will be raised.

 

[Boss]

Should send a note to Moose to have that overgrow entry fixed.

Never mind, I just fixed it to 5.8-6.2

 

[Smokin Moose]

Thanks Boss.

 

[Racefan]

I hope I didn't step on toes by disagreeing with the OG entry but I know 5.5 locks out a lot of elements that require a higher PH to be useable. I believe Moose posted a chart that shows the optimum PH for certain elements recently. Since we can't swing the PH to the extremes to guarantee that all elements are readily available we have to come to a happy medium that allows most to be used with the others sneaking in a little at a time.
Thanks for changing that entry though guys. Hopefully it keeps another newer grower from killing their plants. I hope your 1 baby is a lady and makes it Marley. I'm not here to argue with anyone. Only help.

 

[Marley Man]

yup it should be a female (feminized big bang from greenhouse seeds). I am guessing that it is an anomaly that it has survived. I also have one other seedling that was never put into a netpot, its still in a rockwool tray, and it hasnt really been growing and looks like it will succumb to the same fate.

The rockwool was pretreated for 24 hours, but water was not run through it, so maybe the ph climbed up since all the crap in it was not rinsed out?

anyway, got a 5 gallon bucket and am going to be putting the net pot into that. Also got 5 gallons distilled water and will add a 16th strength of whats on the directions for pure blend pro. I pray that it works.

I do appreciate the responses very much, thank you.

 

[Marley Man]

Ok. Digital camera came in the mail today. So I think pictures will probably help out describe the situation here.

Here is the one plant that survived. Its at least been 8 days since it sprouted, so it is growing slowly:

Whaddya think, think it could handle some nutes?

here are 2 images of the plants that died. No idea what happened to those guys. The one seedling left that was in rockwool and not transplanted also died today.

and here is the new setup. (still have to spray bucket black and aluminum foil tape the lid)

 

[stonar]

i would have kept them out untill the roots were showing and then put thenm in were the cubes holding any water at all when they died?

 

[Myzz617]

Any luck getting anything going? The roots should be visible before transplanting. You need to root them for about 3 weeks before they will be ready to hit the Veg stage.