LED HPA Grow Room 🌱 💧 🔨

[Northern_Loki]

Light spectra, that would be my first thought as well. Anthocyanin development?

Purple, not brown right?

[SuperiorBuds]

@Northern_Loki

Light spectra, that would be my first thought as well. Anthocyanin development?

Purple, not brown right?

Correct, they were purple. I hadn’t thought about it, but the plant that showed this was next to two outside walls – so perhaps it was a bit colder in that corner, too… Just spitballing here really, but we’re moving the entire set of beds into a more central location of the room for this next run, so hopefully that can eliminate some of the variables.

–

We have started to clean up the room from the last run – and there are lots of good lessons to be learned from taking this to the end. The OC had developed some extensive root rot in the center of the root mass while the BK had stained roots, there was no rot, slime, or smell. I am going to attribute some of this to my nozzle placement causing excess water build up. I had the nozzles far too high in the chamber and this was causing quite a bit of spray to hit the bottom of the lid. This caused build-up, which then dripped large drops directly onto the roots. Couple that with too frequent of a spray and some dirty PVC and I think that all added up to problems. I’ve picked up some HTH pool shock and will be running a much cleaner res / system next run.

I have ordered quite a few new products for the next run.

New Aeromist nozzles, the same ones @anon32470837 is running now w/ swivels.
https://www.aeromist.com/low-pressure-ss-303-anti-drip-misting-nozzle-024-x-10-24.html
https://www.aeromist.com/misting-nozzles/nozzle-extensions/nozzle-swivel-connector-10-24.html

I have also picked up some new tees for the nozzles and will be picking up some 1/4" SS tubing to replace everything after the solenoids. Speaking of solenoids, I picked up 10 more so I have some spares and so I can go ahead and switch this from 1 per 4 nozzles to 1 per 2, with a much shorter (8") run.

We’ve begun reworking the feed lines, as well. Before I had a single 3/8" polyethylene line that split into 3 1/4" lines – one for each bed. With the rework on the solenoids I wanted to ensure I had stable pressure all the way down the system, so we’ve ordered a bunch of 1/4" John Guest to 3/4" NPTF fittings. This allows me to run a pressurized 3/4" PVC line all the way down with standard PVC tees to feed each solenoid. This should give me much more stable pressure.

The last piece of the puzzle will be hooking up the new res and pump that will recycle the water through each bed and back into the res. This will act as both a root zone cooler as well as a way to handle the heavy feeding that takes place later on in the plants life. (This replaces the E&F secondary zone I had setup last time to keep the big girls alive.)

[SuperiorBuds]

While I was away the new batch of solenoids arrived.

Along with the nozzles, swivels, and tees. (You’re right, @anon32470837-- Aeromist ships quick as hell.)

The tees I found seem to work, but we’ll see how they do under pressure.

Amazon.com: Dreamtop 10pcs 1/4" Slip-Lok Misting Nozzle Tees with 1pc Plug for...

I was also able to finally pick up my latest reservoir while I was travelling, since everyone was out of stock up here.

I still have a few plumbing items to pick up but at this point most of the items are on hand and we can begin the rebuild this week.

[anon32470837]

Nice! Dont forget - you might want to keep those solenoids under about 118 PSI. Ive had no more failures since dropping down to under 110 PSI max with the pressure reducer.

My new nozzles were due in today, but are a no-show

I will be sticking the C99 seed in my system shortly, so better get ready

[SuperiorBuds]

@anon32470837

Nice! Dont forget - you might want to keep those solenoids under about 118 PSI. Ive had no more failures since dropping down to under 110 PSI max with the pressure reducer.

Good thing to remember for sure. I run at max 110 so I should be good, but you having one fail really made me double-check me backup supply. I now have 4 spare solenoids…just in case.

@anon32470837

I will be sticking the C99 seed in my system shortly, so better get ready

Haha for sure man. Looking forward to it – I will say you’ve really done a good job dialing in your stuff lately though, hopefully I don’t have as much of a rough start this time as last. LOL.

[SuperiorBuds]

I’ve been contemplating this statement quite a bit lately.

Adventures in Hydro #2 - LP Aero/NFT mash-up - or - switching to HPA?

Just thinking out loud here, but are you sure you want your tubs 100% air tight? You need some fresh air exchange in the chamber to help aerate the droplets, plus the roots need O2. Atomizer talked about that at one point. When he was using air tight, rigid foam to build chambers, they needed a way for air to get in and out. He said it was typically the drain pipe, and leaks around the net pot that provided the air exchange, but that those same air leaks around the net pot could cause ai…

To head off any problems I wanted to make a simple list of thoughts to consider for healthy roots. If anyone disagrees with anything or feels I missed something important please chime in.

• Roots need O2 (air exchange)
• Roots hate light
• Root zone temp matters
• Too much airflow will cause air pruning of roots
• HPA mist will escape if you have big leaks
• Contaminants in the root zone can lead to rot or other problems (pests)

Since my root zone is a sealed chamber with a PVC drain back to the reservoir I believe the only issue I will have to focus on will be air exchange. When I originally designed this I had assumed that the highly oxygenated water going through the nozzles would provide enough O2, but re-reading Atomizers threads got me thinking this probably isn’t enough.

This next iteration of the system includes a constant waterfall travelling down 3 sides of the chamber, across the bottom, and out the drain. This is the same water from the reservoir and is meant as a way to cool the root zone and provide a secondary heavy feeding source when roots reach the bottom. While this will provide a source of dissolved oxygen once the plants reach that point it still doesn’t help circulate the air in the chamber itself.

I kept reading the different ways people handled the air exchange when I came across a discussion about maintaining positive pressure inside of the root chamber. I already have a good outlet for excess air via the drain so I started thinking about ways to introduce fresh, clean air into the chamber without creating too much airflow to cause pruning.

I already have a good air pump running to the reservoir and it just happens to have an adjustable manifold on it with extra ports. As a test I went ahead and picked up a few items to play with.

Since I will want to be sure the air I’m introducing is clean I picked up some cheap little in-line HEPA filters.

Amazon.com: Hepa Sanitary Air Filter (in-line) (2): Industrial & Scientific

Then another manifold so I can restrict the airflow even further after the filter.

Amazon.com : QMseller 2pcs 3- Way Aquarium Chrome Metal Gang Manifold Air Line...

Right now I’m not sure how I’ll introduce the air into the chamber, but I’m thinking of a diffuser – perhaps turned upside-down so there’s not a constant flow hitting the lower roots.

Amazon.com : OWUDE Aquarium Bubble Stone, Round Air Stone Bubble Plate for...

As I was writing this up I noticed @HappyHemper and @MicroDoser discussing this very thing over on Larry’s thread.

Adventures in Hydro #2 - LP Aero/NFT mash-up - or - switching to HPA?

I guess you are right, as you said, sterilize the air and pass a ton of it under positive pressure. Anything is possible, just a matter of time + resources + effort. Maybe I’ll try that on the next round – blow through a UV and HEPA, seal the net pots. Or try first with bennies, then see. Sterilizing air and keeping a positive pressure in the root zone is a lot of work; and makes maintenance a bigger chore still. Maybe one day. Not sure about HPA sterilization - that’s @anon32470837’s department,…

So now I think I’ll have another fun test to play with during this next run. I plan on running the same two clones again so I can compare vs this last harvest, but maybe I’ll add a second BK in the third bed and use that to play with air. Or maybe I’ll just go all-in, who knows…

[anon32470837]

Interesting idea. Im in a rush at the moment, so just a quick first thought - I think you will need to have some way for the ‘fresh air’ to be at or near 100% humidity, before it goes into the chamber, or you risk drying the roots out.

I think the diffuser idea is good. Id make it as large as possible to spread out the fresh air and keep the flow rate low.

More later…

Oh, one more quick thought on your root temps - I wonder if your runs of 1/4 tubing were pre-heating the water before it got to the sprayers?

The water in the tubes would tend to be at least at room temp by the time it moved from the warm rez (no chiller in the HPA rez?) to the nozzles, plus the lights would tend to warm up the dark tubes even more.

Ive been racking my brain trying to figure where your higher chamber temps could be coming from, and thats the only thing I could think of.

[SuperiorBuds]

@anon32470837

I think you will need to have some way for the ‘fresh air’ to be at or near 100% humidity, before it goes into the chamber, or you risk drying the roots out.

Ah very good point, hadn’t thought about that. That does bring up another strange idea though.

I just got back from visiting my mother and you mentioning air humidification made me think of her oxygen machine. It’s just a low-flow bubble humidifier built into those things. It’s cheap enough it might be fun to play with, plus I can just fill it from the RO feed.

https://www.amazon.com/gp/product/B004UTQ4NE

@anon32470837

I think the diffuser idea is good. Id make it as large as possible to spread out the fresh air and keep the flow rate low.

I do wonder if flipping it upside-down into the flow of water from the sides would help, too.

@anon32470837

Oh, one more quick thought on your root temps - I wonder if your runs of 1/4 tubing were pre-heating the water before it got to the sprayers?

The water in the tubes would tend to be at least at room temp by the time it moved from the warm rez (no chiller in the HPA rez?) to the nozzles, plus the lights would tend to warm up the dark tubes even more.

Ive been racking my brain trying to figure where your higher chamber temps could be coming from, and thats the only thing I could think of.

I think it was either this or from sitting in the pressure tank too long. I am going to reduce the runs this time around and maybe I can shield the whole thing in bubble-foil to keep temps down. I do run a chiller on the res, though even that is getting a slight rework this time around. (Separate loop running propylene glycol.) I have also painted the outside of the chambers in a flat black and then covered that with a bright white, plus they’ll still be wrapped in insulation.

[anon32470837]

@SuperiorBuds

I do wonder if flipping it upside-down into the flow of water from the sides would help, too.

Yeah, if the air is bubbling through water, that will help a lot I think. Or that humidifier gizmo - or both

Hmmmm. I wonder how expensive one of those oxygen machines is? Small amounts of humidified O2 would be even better?

@SuperiorBuds

I think it was either this or from sitting in the pressure tank too long. I am going to reduce the runs this time around and maybe I can shield the whole thing in bubble-foil to keep temps down.

Yeah, once you get the flow rate lowered down, the water can end up sitting in the accumulator a loooong time. My “5 gallon” tank only holds around 3.7 gallons, but at my current flow rate, that will last about a week before its empty. Way more than long enough to negate any chilling in the rez. It might be more efficient to just chill the accumulator tank? On the other hand, you do still need to keep the rez cool or it can grow nasties before they ever get to the system, so maybe you need to do both?

Im lucky - my room temps are almost always below 70, so my rez, and everything outside the tent, stays at a reasonable temp.

You have a much more difficult situation to deal with that I do.

[SuperiorBuds]

@anon32470837

Hmmmm. I wonder how expensive one of those oxygen machines is? Small amounts of humidified O2 would be even better?

Oh those things are nasty expensive, like $3k. I’ll stick with the air pump haha.

@anon32470837

It might be more efficient to just chill the accumulator tank

Another good point. Since I have a separate loop for the cooling system already there’s nothing stopping me from running a copper line around the tank. I hadn’t thought about that, but I really think that’d work.

@anon32470837

Im lucky - my room temps are almost always below 70, so my rez, and everything outside the tent, stays at a reasonable temp.

The small room here stays whatever temp I want really. Since we’re so far north it only really gets hotter in there during the late summer. Right now I’m actually heating the room to even keep it above 60. The root zone temp problems were during the summer, though, so I should prepare for that eventuality.

[anon32470837]

@SuperiorBuds

The small room here stays whatever temp I want really. Since we’re so far north it only really gets hotter in there during the late summer. Right now I’m actually heating the room to even keep it above 60. The root zone temp problems were during the summer, though, so I should prepare for that eventuality.

How much trouble would it be to partition off, or enclose a section of the room to separate the plants from the equipment? The lights should keep the ‘plant section’ warm enough when the lights are ON, and the rez, accumulator, etc, could stay at a cooler, safer temp?

[SuperiorBuds]

@anon32470837

How much trouble would it be to partition off, or enclose a section of the room to separate the plants from the equipment? The lights should keep the ‘plant section’ warm enough when the lights are ON, and the rez, accumulator, etc, could stay at a cooler, safer temp?

There are very different issues from summer to winter here. During the summer there are few days of 80+ outside but there’s always high humidity, the air system in the room does a good job keeping that in check though.

In winter it is extremely cold and even a fully insulated room like mine cannot be heated w/ LEDs alone (even with the drivers attached). I also don’t heat the garage the room is located in – so having any water out there would lead to all sorts of problems.

I do have the cooler setup so in the winter it is located in the room to help offset heat costs, but it is relocated outside the room during summer. I won’t really have a heat problem for a few more runs though – well into summer.

I think this run will be a whole other set of challenges due to the season change, but I have enough runs under my belt here now to know about what to expect. I just want to ensure I keep the roots in the proper range this time around, not too hot and not too cold.

[HappyHemper]

@SuperiorBuds

I do run a chiller on the res, though even that is getting a slight rework this time around. (Separate loop running propylene glycol.)

@anon32470837

It might be more efficient to just chill the accumulator tank?

I have another idea… how about using the glycol chiller to chill a tub of working fluid to your ideal temperature, then run a heat exchanger, as simple as a stainless coil, on the high pressure side right before the nozzles? Like a poor man’s beer keg chiller - an ice box with 30’ of line in it.

That way, your HP output to nozzles would be very damn close to the setpoint on your glycol system, and with such low flow rates and long-ish off-times, the solution would have the time to come to temp.

$0.02

[SuperiorBuds]

@HappyHemper

I have another idea… how about using the glycol chiller to chill a tub of working fluid to your ideal temperature, then run a heat exchanger, as simple as a stainless coil, on the high pressure side right before the nozzles? Like a poor man’s beer keg chiller - an ice box with 30’ of line in it.

That way, your HP output to nozzles would be very damn close to the setpoint on your glycol system, and with such low flow rates and long-ish off-times, the solution would have the time to come to temp.

Great thought. I need to lay everything out so I can get a high-level view, but it might be possible to use the waterfall PVC feed line as a cooling loop as well. It’s already feeding every grow bed and the water moves a lot faster through that from the res, and it’s the right temp. Maybe something as simple as running the HPA lines along that and wrapping them both in pipe insulation will help keep the HPA spray cool enough after the accumulator.

Hopefully later today I can get back out there and start seeing what goes where again. I’ve got a 5 year old in the house for the next 2 weeks so it’s been a bit tough to get out there lately and get work done.

[SuperiorBuds]

I am finally back and starting to feel like myself again. I’m buried with some work projects prepping for the holiday shopping season, but I am planning on getting the room together in the coming week or two.

While I was downstate I ran across a brand new Hydro store in Detroit. Amazing shop, like a candy store for growers. With that I picked up a few items even cheaper than I could get on Amazon.

I already have an ActiveAqua chiller but now we’re headed into winter and our well water comes out of the RO system at about 40 degrees. Now that we’re auto-topping the res via the RO system and a float valve I wanted to ensure that the water temps were stable during the coldest months, so I went ahead and picked up a heater to sit alongside the chiller. This will keep the water in the exact range I am looking for.

I also finally gave in and picked up the Bluelab Guardian Connect. I am a data-whore and I hated manually having to go out into the room to take measurements. This also lets me build more automation around things which will be even more important as we move this system into the larger rooms.

I also picked up some short sections of 1/4" SS straight pipe. Everything from the solenoids to the nozzle tees will be SS, so no more hose flexing this time around.

Stainless Steel 316L Welded Round Tubing, 1/2" OD, 0.46" ID, 0.020" Wall, 12"...

Right now I’m waiting on someone to come out and fix a problem with the house water system before I can continue. I am only getting 20-30psi from my home accumulator (bad pressure switch). With that low of pressure I can’t run the RO w/o a booster pump, so I’m at a standstill until that gets corrected.

Almost every other piece of the new setup has arrived now. I just need to build a new enclosure for the two reservoirs and chiller then plumb up the SS cooling loop – then we can finally move into the room. Still need to add a new light rail on the ceiling and setup the valves so we can auto-drain the system, but it’ll all move quick once I really start going.

[anon32470837]

You’ve got a lot going on there! Good luck and keep us posted

[SuperiorBuds]

The room is now fully disassembled and everything is soaking in a strong bath of cleaning solution. I have the new reservoir placement all mocked up so I am ready to begin building the new workbench in the garage that will house and hide the entire water system. Moving the res outside of the room allows me to relocate the chiller (which was heating the room) and also keep the large volume of water away from the light and heat of the room. I also can then monitor and change water w/o opening the room – so nighttime res changes are possible once again.

I have a few more parts incoming that will finalize my heating/cooling loop. This took a bit longer to find exactly what I was looking for – but I believe I have what I want now. Taking a cue from the home-brewers I found this gem.

Temp Control Coil | Spike Brewing

I was worried about just dropping the SS coil into the tank, especially since the loop I bought before was 10" in diameter and the inlet to the tank is only 5". With this I can install a 4" tri-clamp fitting to securely mount the coil to the res, keeping it sealed from dust/debris while also holding it tightly in place.

Unfortunately the biggest issue I’ve had in getting restarted this time around has been other people. I’ve been waiting more than a few weeks now on a contractor to come over and complete some work in the room. He’s going to run all new electrical so I can eliminate some extension cords, but those could wait if needed. Really I am waiting on him to replace the old water heater that’s taking up so much space with a small new on-demand unit. (I’d do this myself, but I am not messing with LP lines.) And lastly he is replacing the pressure switch on the house to fix a problem I’ve been having, then tapping into the water in the room and installing the RO system. This is the problem with living in a very, very small town in the middle of nowhere. I have to rely on locals for some of the work…

Really hoping that after Thankgiving I can light a fire under their asses and get this knocked out. I’m dying to restart this monster!

[anon32470837]

Sounds like it will be an awesome setup when you get it done.

Im really curious about those new nozzles you have. Do you plan to run some flow tests and hang time tests with them?

Thats a bummer about the contractors. Been there and done that, so I sympathize.

[SuperiorBuds]

@anon32470837

Im really curious about those new nozzles you have. Do you plan to run some flow tests and hang time tests with them?

I am planning on it, yes. Last time as soon as the system was tested I had clones dropped on me, but this time around I’m taking it much slower and making sure I get everything exactly where I want it before I start the run. I’m going to resist all of the external pressures and make sure I can fully test everything before starting.

@anon32470837

Thats a bummer about the contractors. Been there and done that, so I sympathize.

Yeah small-town BS sucks for sure. Got into it with the guy last night at the bar, so looks like I’ll just take the hit and find someone else who can actually show up to do the jobs. I seriously cannot stand slackers…

[SuperiorBuds]

Every year it seems like the same thing. I spent nearly 6 months prepping for holiday web traffic, making sure the servers were going to be good to go and that our production facility would be able to keep up with demand. We were in a great place…I thought.

Then holidays hit, traffic is up 4x from last year, we’ve hired an additional 350 people, moved to 3 shifts running 24/6 (with one day a week for machine maintenance), and we’re keeping up, but it’s taking a LOT of my time.

I will get back to the grow room soon. I swear…