A few questions about hydroponics... Please help.

My friend has a new setup, he's a legal patient and he is staying within the legal guidelines.

He has a 1000 Watt MH aircooled hood above 6 Sour Desil clones. At the moment the light is about 3-3.5 feet away from the clones and is ran 24 hours a day. He got the clones for free but when he got them back to his house he thinks they were shocked into flowering because they already have hairs showing and they are no more then 5 inches tall.

He has a DWC hydroponics setup that he made himself. Its got 4 Airstones in the bottom of the DWC reservoir that are running constantly. It produces a good amount of bubbles, nothing wild.

He was having a little bit of trouble controlling the temperature of the DWC reservoir. He is worried that since the reservoir was a temperatures of 80-85 for 3 days that Bacteria and rootrot might start to take place. Would it be a good idea to just throw out all the reservoir water and start anew, or since it was only 3 days and now the temperature is down will it be okay just to change out the reservoir at the end of the week?

He also wants to know, would it would be a good idea to spray the roots with a Hydrogen peroxide solution once every other day or so just to protect them? Also would adding some type of alcohol help kill bacteria or root rot?

He also adds 2 1/2 tsp of Hydrogen peroxide for every gallon of water. Thank you for helpful replies!

the hairs could just be that they were cuttings taken from a flowering plant

That's true, he's thought they might have just been taken from a flowering plant.

But please someone help with the resevoir questions, thank you!

As long as the temp in the reservoir aren't that high it should be fine. And putting the peroxide in the water is good enough he shouldn't spray the roots.

Thank you very much.

He also plans on topping the plants, should he do this while they are small, or wait a week or two before flowering?

I FIMed mine at about 8 inches tall and like to get the new tops a good start before I put them into flowering

Thanks again, he might have to Top them soon. Most of them are above 5 inches.

Now he's got the temperature of the reservoir to 68-74 and pretty stable. For some reason after adding lemon juice or vinegar to lower the PH 2-3 hours later it'll be back to 7.5-8 and he knows that's to high.

He thinks the problem might be because he added baking soda once to raise the PH, but he hasn't done that since.

Is there a more reliable way of lowering and stabilizing the PH to 5.5-6 besides vinegar and lemon juice?

Also since he's having problems with the PH should he just change out the reservoir water and start from scratch? Or should he just keep trying to adjust the PH and change out the reservoir in a week?

Onxx14 said:

Thanks again, he might have to Top them soon. Most of them are above 5 inches.

Now he's got the temperature of the reservoir to 68-74 and pretty stable. For some reason after adding lemon juice or vinegar to lower the PH 2-3 hours later it'll be back to 7.5-8 and he knows that's to high.

He thinks the problem might be because he added baking soda once to raise the PH, but he hasn't done that since.

Is there a more reliable way of lowering and stabilizing the PH to 5.5-6 besides vinegar and lemon juice?

Click to expand...

There are chemicals you can use from the hydro shops, PH up and PH down.

Moved down.

Maximus cannabis said:

There are chemicals you can use from the hydro shops, PH up and PH down.

Click to expand...

True, I forgot to say he was looking for things he might be able to pick up at the super market or find around his place.

Thanks for the reply.

He also remesured the distance from the light to the plants and said the 1000 watt MH is only 2 ft 3in away from them. Is this to close? They don't seem to show any heat damage yet and his hand doesn't even get hot at all really if its held above them even for awhile.

I also forgot to ask should he adjust the PH of the water that is used to mist them? And how often should he mist the plants with distilled water?

OK, let's not overthink this. He should aim to keep the res temp 65-70. This not only inhibits pathogen growth, but colder water holds more oxygen in solution.

For PH control, he needs some General Hydroponics PH Up and PH Down. Forget lemon juice, vinagar, baking soda, etc...Use the right stuff. It's cheap, consistant, and lasts a very long time.

Lose the peroxide. Change the water once/week. Check and adjust PH and TDS every day. Use RO water for everything if possible.

If the plants are small and weak, the light should be about 48" away. Slowly bring it down till its about 24" away. Wait till there is a good root mass before brining the light this close. If there is a decent root mass, spraying shouldn't be necessary. If he wants to foiler feed (I don't), he should PH the water and feed at about 400ppm.

I run a 5.5 PH in Veg and around 6 PH in Bloom.

With the small plants around 800ppm should be good to get started. Slowly bring it up to around 1000-1200ppm. Too little is way better than too much. If there is any leaf tip burning, reduce ppm.

Now, what about temp and humidity? He should shoot for 75 degrees and 50% RH during the day. At night 65 degrees and still 50% RH. I like to reduce the RH to 40% during bloom to help stop powdery mildew.

As long as he has at least 3 healthy growing nodes, he can top anytime.

How bout some pics?

https://www.rollitup.org/indoor-growing/407048-20-000-watt-medical-grow.html

Thanks for such a detailed reply collective gardener, I really appreciate the time you took to reply to my thread.

Unfortunately they are my friends, not mine and he won't let me take pictures of them. I am only posting on his behalf.

He raised the light a bit, and will start taking it down slowly.

How important is the RH during veg stage? He completely forgot to get a meter for RH, he was waiting until Flowering because he didn't think it was important until then.

Are you sure its safe to bring it up to 600 PPM? They aren't much taller then 5-7 inches and they were shocked into flowering so he's waiting for them to pick up on growth again.

First off stay away from using lemon juice & vinegar for ph control & get some proper ph up & down,using cheap homeade remidies will make the ph fluctuate way too much & the plants suffer.

Also until you get more experience growing stay away from peroxide,especially the brands sold in hydro shops which are generally 30% compared to the standard 3% peroxide sold at regular stores,you can & most likely will burn the shit out of your plants,having roots that are pearlly white is over rated & not a must to pull off a kick ass harvest your first time out.

What you can do is to rinse the roots in clean ph'ed water before putting them back into a fresh res,this will keep most the scum off them & help whiten them up,i'd be willing to bet that most of the discoloration of the roots is a direct result of that lemon juice your using which allways creates a hell of a scum on roots & in the res.

As for the clones having pistils showing on them all that means is that the clones were taken from a sexually mature female, moreso than the clone being taken from a flowering plant,most plants will show heavy amounts of pistils after they are 6 months or older, even with 24 hrs light.

Thanks for the response panhead. I really appreciate the help, thanks for your time.

The roots look white, and he didn't ever see any signs of root rot, he was just trying to prevent root rot by using the standard 3%.

He did see some scum in the reservoir this-morning when he was checking the PH. He thought it was because of the nutrients, but he stopped using all the lemon juice and vinegar and got some real PH down.

Should my friend just chang out the reservoir with fresh water and nutrients since he used that lemon juice and vinegar or just wait until he changes the nutrients at the end of the first week?