HPA Without An Accumulator

PetFlora

Well-Known Member
I thought I had started a thread here as several peeps answered it. Turns out it was merely a Suggestion Box type thread where I 'suggested' HPA is different enough to deserve its' own sub forum.

If I get enough interest I will start a journal here as I have 5 seedlings (1.5-2.5" tall) in my DIY bubbler.

As a personal use grower, I am looking for the benefits of HPA without adding an Accumulator. How close can I get?

Smart Products is one thing I tried to resolve the problem of pressure drop in between feed cycles, which is what an accumulator resolves. How big a difference will that make when my feed cycles are 3 seconds, (where the first <1second is not full pressure), none of the accumulator growers has answered that for me. Smart Products was kind enough to send me several sets of samples, but each time the quick ramp up of pressure blew them apart. But that was over a year ago; since then they have introduced a lot of new items.

In the mean time my basic system utilizes Reptile Basics advanced mist kit
and upgraded to the Aquatec 8800 but WITHOUT their timer. I use a Sentinel, which is not 100% accurate at one second, which is not that necessary unless you are using an accumulator. I find the single or double mist heads is all I need in an 18G Rubbermaid tote. I am using 2 single head misters at opposite ends and opposite sides to help swirl the mist. I am still playing with on/pause times. Right now I am 3 seconds on- 2:45- 2:30 seconds pause. I watch for wilt and adjust in 15 second increments until it stops.

I am on my fourth HPA grow, the first with all hardware in place from the beginning. It is my first using DM nutes (Gold: Zone, Ad.27, Silica, Grow/Flower A & B). I find DMs nute calculator 25% more concentrated than my Hanna TDS meter says. So far I am happy with DM nutes, but find DM not too helpful (will consider H &G when I run out as peeps here are impressed with their customer service. I tried to push past HPAs recommended flower ppms (~1000) only to get some leaf tip burn, so I dialed back at least until I get some pistil clusters and bud development. If I understood Fatmans' comment on another thread, having them too hot may have actually held bud development back. Made sense once I thought about it.

Plant size is important to know, as the roots will be as long as the plant is tall. Ample depth is required to prevent tap roots from pooling on the bottom of your root pod; a 3 ft plant has 3 ft roots= 6ft, PLUS you need room under for drainage and over for lights. Also, o
f great importance is realizing that when roots are provided with lot of air space the nutrients can swirl and cover them better. Logic tells me, the more roots that can get misted, the faster, bigger, and greater the bud development. I am now experimenting with AF's to resolve height and depth issues, and to harvest from seed < 75 days. Alas, the seeds I bought privately are not stable. I am over 3 months with barely any signs of pistils.

Hope you will join the adventure. Haters please move on.

 

PetFlora

Well-Known Member
Nute Expense is Relative to number of plants/mist heads per grow. Due to small feeding portions < 3 seconds ~ every 2-3 minutes 24/7, nute strength is much lower. I usually run 2-300 ppms in early veg and raise weekly to 6-800 in late veg (AFs are a different dynamic). Flower from 600-1300 depending on nutes as well environmental factors. Check for tip burn and adjust accordingly. This grow I am using all Dutch Master Gold- Silica, Zone, Add.27, Grow and Flower A/B.

I mix 5G at a time, which now lasts 4-5 days. I am using 2 single heads growing two AFs, but have 5 seedlings backing it up- won't know how many females for 2-3 weeks. DM offers 5 Liter jugs for bigger growers. Keep in mind you can recycle up until about the 3rd week of flower. So you are only looking at ~ 5 weeks of D2W (Drain to Waste). I feed the leftovers to my outdoor plants, which love it.

During flower cycle the chemistry of the female plants changes radically to support bud development, much like a pregnant woman. The nute runoff becomes quite toxic in both pH and ppms. Recirculating these nutes will contaminate the rez, and eventually sicken the plants (roughly 3 weeks into flower first signs appear). The signs appear as nute deficiencies, causing people to add more nutes, which only adds fuel to the fire.

Equipment: Small RV pump (available in AC or DC). Check out Reptile Basics. During Pod Racers journal (some 8-10 years ago, they were blowing pumps up left and right). I have been using a Aquatec 8800 pump ($90) for two years http://aquatec.com/boost.htm , plus single and double mist heads (depends on plant/root size), fittings: get a quick release pet cock drain plug for the rez, and a Y splitter (one each per tote) and tubing. All under $200. I use a Sentinel MDT-1 timer (~$130), inline filter (~$20), rez was a donated 35 pound kitty litter containers, you need extras for premixing nutes) tote price depends on size.

Totes: Rubber maid type. I have not yet found the ideal shape, which would be taller than wider, in search of 20-30G garbage pails. I recommend one plant with a max grow height of 2ft per 18G Rubbermaid tote. Once you see how big the root mass gets in flower you will understand. Keep in mind you need plenty of air space around each root so the mist can rise and fall 360 degrees. I rotate my PVC coupler 180 degrees several times a day for assure max root misting coverage. If growing 2 plants in one tote, put one single mist head on each long side at near opposite ends. Now, if you plan to SOG short plants, you might get 6-8 in a 30G tote- < $15.

hth
 

PetFlora

Well-Known Member
About 2 years ago I found Pod Racer's extensive blog. I was intrigued, but I had to read it 3 times, partly because these guys were pioneering it for mj, and were on a whirlwind learning curve, plus Pods esoteric rants.

As to be expected when pioneering, some of the assumptions were wrong, like the N dumping, which was probably nothing more than recirculating toxic runoff due to hormone changes during bud development.

Pod Racer called it "TAG", I call it High Pressure Aeroponics (HPA) and there is at least one significant variation. I am a personal use grower,so the system you see pictured here is of 2 totes (eaach tote can hold 2-3 AF plants. The pump can probably handle 4 totes. For largeer grows, consider installing an Accumulator.

Although you could grow trees with HPA (55 G drums) , it's particulary suited to SOG. Why? Root systems are as big as the plant. If you have a 5-6 ft plant you need a two foot cushion all around to mist the entire root mass. Also you need sufficient room below to keep the drain clear.

Relative Humidity RH inside the root chamber is improtant. Too much and you will soon get gnats, mold, algae, fungus...

If RIU puts up a HPA forum, I will start a journal.



1. The system in place. Note inline filter (200 mesh screen) between rez and pump


2. PVC couplers come in a variety of sizes. The one on the far left has shortest thread and largest opening. Makes it easier for nutes to get up in there. I almost lost 5 young plants using the others.



3.PVC couplers with neoprene puck. Note the ledge inside will prevent the plant from falling through once it gets heavy- and it will!



Roots tend to develop before you see much top growth

This was taken a week ago (9'). This plant was on death's door. I credit HPA with bringing it back. It is now over 12".



You won't find these roots in any other aero/hydro system, and they are not the best. When the root chamber is totlly dialed in, all those hair like roots will fill with fuzz that are called root hairs. The fuzz significantly increases the surface area, allowing for more nutes to be absorbed at each feeding.

 

PetFlora

Well-Known Member
Although HPA is 'hydr/aero', it has little in common with conventional hydro/aero. I attempted to adapt a low pressure pod with low pressure pump to high pressure using a high pressure pump, but low pressure mist heads, and long cycle timer. The results were better, but no cigar. You need high pressure pump/ mist heads and a deep cycle timer before your roots will develop properly.

Pro HPA growers focus on their roots instead of the plants.

My journey to HPA: I started with Drip, then bubble, then low pressure mist (with entirely too long feed cycles) and finally to HPA.

In HPA you do not use any medium beyond the seed starter cube. If working with clones, you simply insert them into neoprene pucks (which fit perfectly inside PVC couplers), and let them dangle. Until roots develop you will likely use longer mist times

What sets HPA apart is optimal nutrient uptake. Only HPA delivers the nutes to the roots as a fine mist- bite size droplets (20-50 micron) that are readily absorbed. As roots can only consume so much per feeding, a deep cycle timer (<2sec) is required to dampen the roots, not soak them as all other DWC systems do. Within ~ 2.5- 3 minutes they are dry enough to feed again- 24/7. When parameters are kept within range, root growth is explosive which is followed by plant/bud growth.

Do not recirculate nutes after 3rd week of flower.

Relative Humidity inside the root chamber is as important as rez temp (50-70 degrees). Much above 75% RH and it becomes a breeding ground for gnats, root rot, etc
 

rosecitypapa

Active Member
Thanks for the pics, Petflora! Nice writeup, pretty informative and I like the novel 'net pots'. I have a couple of questions.

Is that a 3/8" water line that you have running in your system of 1/4"?
Where the water line enters the tubs, is that simply a grommet or is it a fitting?
Do you have any pics of your mister placement inside your tubs?
What is the fitting you used to connect to the kitty litter rez?

Thanks!
 

Mike Young

Well-Known Member
When you say, "do not re-circulate after 3 weeks into flower" would that apply to peeps with larger res's? I run 20-25 gallons for my 2 plants I have now. I like having the larger res, as it's easier to maintain, and needs to be changed less frequently. Eventually I wanna try filling my res to the top, which I think I could get 60 gallons or so, just so I don't have to mess with it for awhile.

Thanks!
 

PetFlora

Well-Known Member
Keep in mind by recirculating, you are basically peeing in your own pool. During veg and early flower it's not that big a problem. However, when the ladies turn motherly, their hormones rage- just like..., well you know.

During early bud it's still not much of an issue, but after a couple weeks, begin to chart your runoff pH & ppms. This was recommended to me by a seasoned aero grower. I was shocked, but it's only for 3-5 weeks so with a 5G rez, it's not a big deal. Why is your rez so big for 2 plants... whatcha growin, trees? hth
 

Mike Young

Well-Known Member
I'm not sure I understand how re-circ compares to peeing in the pool? If I had probs with root rot, I could see not wanting to spread that nastiness. You're saying that hormones are released from the roots? I thought they're job was to uptake.

I've read that there's a sweet spot in the ppms that will give you stable ph... Still working on that one.

I do hope to grow trees, yes. The res is big cause I was hoping to not have to change it out every week. Not my favorite thing to do. I've heard of people never changing their res and getting very respectable results. I'm sure results could've been better. But I'd like to settle in the middle somewhere. Res change once per month???
 

PetFlora

Well-Known Member
I think you misunderstood. A females' hormones change radically in bloom. During this time there is a huge increase in P-K, and therefore increased waste which is released via the roots. This waste significantly raises the pH and the ppms of the runoff. Recirculate at your own peril.
 

PetFlora

Well-Known Member
Thanks for the pics, Petflora! Nice writeup, pretty informative and I like the novel 'net pots'. I have a couple of questions.

Is that a 3/8" water line that you have running in your system of 1/4"? All tubing fittings and mist heads purchased from Reptile Basics.
Where the water line enters the tubs, is that simply a grommet or is it a fitting? The tail of each mist head fits tightly inside the tubing, or use 't' fittings
Do you have any pics of your mister placement inside your tubs? No, but they are low on the sides vertical to the mid root- firing up
What is the fitting you used to connect to the kitty litter rez? Drain Plug with pet cock also purchased from RB. hth

Thanks!

All your answers are next to your questions. I m adding this as a popup says my answer is too short. hth
 

PetFlora

Well-Known Member
In another thread, Atomizer suggested my feed time of 3 seconds was overfeeding my roots. Due to almost losing the plants (their roots were on deaths door) the size of my roots does not truly reflect their age. The small plant has 4 times the root volume as the big one, but the top is half the size of the big one, whose roots are growing daily. During the last week or so I have been adjusting pause time based on the 3 second feed time. Just before lights out last night I cut the on time to 2 seconds and set pause to 1:35. Throughout the day I have been adjusting up to currently 1:55 pause with no sign of wilt. TBC.

If you see an Atomizer post, please send him here. His input is appreciated.
 

PetFlora

Well-Known Member
Following Atomizer's lead, today I experimented with cutting my feed time from ~3 seconds to ~ 2, playing with the pause I started at 1:35 and each hour increased it to an hour before lights out 2:00.

Interesting development began showing up late this afternoon. Both plants started to look like they do shortly after I FF with DM LL/S. Virtually all leafs are reaching up stretching toward the light. Whee is Atomizer when I need him to explain this????
 

Bob Smith

Well-Known Member
Following Atomizer's lead, today I experimented with cutting my feed time from ~3 seconds to ~ 2, playing with the pause I started at 1:35 and each hour increased it to an hour before lights out 2:00.

Interesting development began showing up late this afternoon. Both plants started to look like they do shortly after I FF with DM LL/S. Virtually all leafs are reaching up stretching toward the light. Whee is Atomizer when I need him to explain this????
Something tells me the "haters please move on" might've turned him off; I know that I took it as directed at him (not that I consider him a hater).
 

PetFlora

Well-Known Member
Small plant was a touch droopy this morning, so I cut pause time back to 1:50. Will keep an eye on it.

BobS I hope not. I give usually him his props wherever he provides input. Pretty much the only place we disagree is on whether mine is HPA, and that only because full pressure is not instant as it is with an Accumulator. I'm gonna PM him

Photo update.

Big Girl (Sat dom) is now 17.5". 12" Indica dom.

Root mass in front belongs to the 17.5. You would think the opposite, right? New roots developing all over. Amazing to think such few healthy roots are supporting this plant.

And finally pistil development starting to show up. I can believe the slowness of these AFs was partly due to sick roots.
IMG_0755.jpgIMG_0756.jpgIMG_0754.jpgIMG_0757.jpg
 

rosecitypapa

Active Member
PetFlora, thanks for your answers. In the pic of the root mass on the left, what is that white stuff at the bottom of the pvc plant holder?
 

PetFlora

Well-Known Member
rosecitypapa: it's a S2G starter cube. A minor issue: the neoprene puck I used is from a previous grow. IMHO, neoprene pucks were designed for cloning, not growing; once the roots are established, the clones are removed to some other device. While the neoprene gives, I don't think it was intended to collar a fat main stem.

Although it may not be necessary to enlarge the hole,
I opened up it up. My concern is not doing so could choke the main stem enough to prevent nutrients and waste from flowing properly just inside the bark area. The hole in this puck is still a little wider than the main stalk at this moment, so the weight of the plant is pushing the main stalk through the puck making the S2G cube visible. hth
 
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