Can I have it too humid in my humidity dome for germinating?

Sam&Max

Sam&Max

Active Member
Hi,
my humidity dome is now filled with over 230 starter cubes (rockwool) which I soaked with tap water before putting the seeds in them.

Temperature in the dome is set at 27 degree celsius or around 80 degree Fahrenheit.

Now I worry that my cubes are maybe too wet or that the humidity in the dome could be too high?

Is it possible that my seedlings rot and my cubes start to mold?

How often do I need to vent the dome? There are ventilation holes. At the moment I have them closed. Once per day I remove the lid of the dome for 5 minutes and let the air exchange.
 
Esrgood4u

Esrgood4u

Well-Known Member
Sam&Max said:
Hi,
my humidity dome is now filled with over 230 starter cubes (rockwool) which I soaked with tap water before putting the seeds in them.

Temperature in the dome is set at 27 degree celsius or around 80 degree Fahrenheit.

Now I worry that my cubes are maybe too wet or that the humidity in the dome could be too high?

Is it possible that my seedlings rot and my cubes start to mold?

How often do I need to vent the dome? There are ventilation holes. At the moment I have them closed. Once per day I remove the lid of the dome for 5 minutes and let the air exchange.
Click to expand...
Rock wool is NOT ph stable. You should always soak the cubes in PhD water over night then lightly squeeze the water out of the cubes and if possible repeat the process.
A humidity dome you can leave open the vent constantly and you will still keep a higher than normal humidity level.
A humidity of 65 is what to aim for with seedlings but to be honest they will grow fine with much lower humidity. I don't use a dome at all. Germinate the seed then straight into whatever medium I'm using straight under my lights.
 
Sam&Max

Sam&Max

Active Member
what do you mean by ph stable. The ph will change every day?

I got cultilene rockwool which you don't need to prewash (like the grodan stuff). But you don't mean that?
 
Esrgood4u

Esrgood4u

Well-Known Member
Sam&Max said:
what do you mean by ph stable. The ph will change every day?

I got cultilene rockwool which you don't need to prewash (like the grodan stuff). But you don't mean that?
Click to expand...
I mean the rock wool cubes need soaked in PhD water to bring it to the correct level. I've soaked in ph 5.8 water before and squeezed the water from the cube and retested it and it jumped up to 6.8. It's worth soaking them once or twice so the rock wool doesn't push the ph level up. http://www.fullbloomhydroponics.net/how-to-prepare-rockwool-cubes/
I'd still pre soak just to be sure. You'll get a surprise I think that the ph will jump
 
K

KryptoBud

Well-Known Member
Sam&Max said:
Hi,
my humidity dome is now filled with over 230 starter cubes (rockwool) which I soaked with tap water before putting the seeds in them.

Temperature in the dome is set at 27 degree celsius or around 80 degree Fahrenheit.

Now I worry that my cubes are maybe too wet or that the humidity in the dome could be too high?

Is it possible that my seedlings rot and my cubes start to mold?

How often do I need to vent the dome? There are ventilation holes. At the moment I have them closed. Once per day I remove the lid of the dome for 5 minutes and let the air exchange.
Click to expand...
Having a dome over them really isn't needed,
 
Sam&Max

Sam&Max

Active Member
The dome is only for temperature? Anyway, I got rid of the lid.

Now it is too late for presoak. And I am not going to start squeezing the cubes with the seedlings inside them. What a crap. The tap water I gave them has a ph of 7.1. I thought my device was not properly calibrated so I used the some test strips and the ph lower showed than it is. But after calibrating it shows 7.1. So do I need to soak the rockwool cubes now with ph adjusted water? I mean they are still very wet from the first soak. Is it possible that the plants or seeds can drown or rot in the rock wool or is that not possible? If it isn't possible it would be fairly easy then to soak them again in ph adjusted water. What does it need to be 5.5?

Many of the seedlings already came out. Do I need to direct a fan on them so they get stronger. Or is it too early for them?

I am worrying that they stretch too much. But I have 2 x 39 W t5 bulbs 24 hours on. So that should be alright.

When should I start feeding them small amounts of nutrients and give them water? When should I reduce the amount of light to 18 or 20 hours?
 
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Esrgood4u

Esrgood4u

Well-Known Member
Sam&Max said:
The dome is only for temperature? Anyway, I got rid of the lid.

Now it is too late for presoak. And I am not going to start squeezing the cubes with the seedlings inside them. The water that I gave them was 6.0 - 6.5.

Many of the seedlings already came out. Do I need to direct a fan on them so they get stronger. Or is it too early for them?

I am worrying that they stretch too much. But I have 2 x 39 W t5 bulbs 24 hours on. So that should be alright.

When should I start feeding them small amounts of nutrients and give them water? When should I reduce the amount of light to 18 or 20 hours?
Click to expand...
The fans will give then strength yeah. Will also drop your humidity even more. They have popped and you have seedlings. I'd be concentrating more on how fast they are growing and the colour they are more than humidity. The ph will eventually level out. Check the runoff ph next time you water them. Some People use t5 lights for the entire grow. You just need them really close. Keep moving them closer and closer until you start seeing negative effect from the lights then back the light off again. You will eventually find the sweet spot. Stop babying them so much. They are a plant that thrives perfectly well without any help from us at all.
 
Sam&Max

Sam&Max

Active Member
I just had to edit my post before. Realized my tap water is ph 7.1. Is there a need to handle that somehow e.g. flushing? (or just reread the edited post before, where I explained my thinking)

Can I direct the fan airflow directly on them? :-/
 
Esrgood4u

Esrgood4u

Well-Known Member
Sam&Max said:
I just had to edit my post before. Realized my tap water is ph 7.1. Is there a need to handle that somehow e.g. flushing? (or just reread the edited post before, where I explained my thinking)
Oscillating is better turned down low. You need to see them swaying and not b
Can I direct the fan airflow directly on them? :-/
Click to expand...
Oscillating is better turned down low. You need to see them swaying and not bending with the wind pressure.
Rock wool dries out quickly. Just ensure you drop the ph to around 6.0. It will eventually sort itself out. Flushing not really needed. What is the final medium going to be???
 
Esrgood4u

Esrgood4u

Well-Known Member
Yeah you really need the ph around 6.0
Just ensure from now on you ph the water. When you do let it sit for an hour or so and re check it. Eventually it will stabilise. When you water them if you can check runoff ph. It should be same coming out as what's going in.
 
K

KryptoBud

Well-Known Member
Sam&Max said:
The dome is only for temperature? Anyway, I got rid of the lid.

Now it is too late for presoak. And I am not going to start squeezing the cubes with the seedlings inside them. What a crap. The tap water I gave them has a ph of 7.1. I thought my device was not properly calibrated so I used the some test strips and the ph lower showed than it is. But after calibrating it shows 7.1. So do I need to soak the rockwool cubes now with ph adjusted water? I mean they are still very wet from the first soak. Is it possible that the plants or seeds can drown or rot in the rock wool or is that not possible? If it isn't possible it would be fairly easy then to soak them again in ph adjusted water. What does it need to be 5.5?

Many of the seedlings already came out. Do I need to direct a fan on them so they get stronger. Or is it too early for them?

I am worrying that they stretch too much. But I have 2 x 39 W t5 bulbs 24 hours on. So that should be alright.

When should I start feeding them small amounts of nutrients and give them water? When should I reduce the amount of light to 18 or 20 hours?
Click to expand...
What you should've done is a bit more planning and research of the basics prior to starting 200 plus rw cubes.
 
Esrgood4u

Esrgood4u

Well-Known Member
Sam&Max said:
ok I did read that I shouldn't fertilize plants until the first set of true leaves shows up! Makes sense.
https://www.thespruce.com/when-should-i-feed-plant-seedlings-1403093

Should I add a small amount of hydrogen peroxide into the ph adjusted water for the seedlings? Or shouldn't i do that now at all?
Click to expand...
I've never used h202 so can't really comment.
https://www.rollitup.org/t/flush-with-h202-have-u-done-it-before.261864/
I found that after a quick search. I don't know if it will help much.
 
Sam&Max

Sam&Max

Active Member
I want to hang my lights up now. I have four ebb and flow tables. Effective grow area is 1.1m 1.x1m each.The tables are in a rectangular room all in one line. the walls begin 40cm from the sides of the line of the tables and are painted white.

I have four medium adjustAWings double ended light fixtures. I will put one fixture over each table.

But do I need to face the reflectors side by side or all in one line???

Here is a layout advice from the manufacturer itself.

https://www.adjustawings.com/products/lighting-kits/750w-de-hellion-lighting-system/hellion-layout-tips/

But still I don't know if I should put them inline or side by side?
 
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Esrgood4u

Esrgood4u

Well-Known Member
Set them out so the plants all get the same amount of light. I'm constantly changing the position of my lights so the spread remains even across the full grow.
 
Esrgood4u

Esrgood4u

Well-Known Member
ANC said:
You don't need a stinking humidity dome for seeds. You want them to be as hardy as possible from the moment they crack that seed.
Click to expand...
A little abrupt and disrespectful. The man is trying to learn and is unsure what is best for his plants. Isnt the whole point in a forum too help each other via our past experiences?? My mother always told me that if I had nothing nice to say then I shouldn't say anything at all. I agree bin the humidity dome as it's not needed.
 
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