Armdog
RDWC GROWER
I agree with this. Aeration is the key. I use a alita linear air pump for my 5 bucket system. AL-40 is what I have and it pounds out the air for a 5 bucket system.
Heisenbubbles Do it yourself RDWC build
- Thread starter Heisen
- Start date
Bc_ca
Super Active Member
here are the pics of the threaded end.
The gasket is 1/4 thick
There is a Oring at the bottom thread for the cap
The thread end has widely spaced turns molded
The cap has a single turn much like a pickle jar
The tech told me that cch20 removed the third flat gasket that sits in the caps bottom groove due to e xactly what HB states “can’t seal threads”
So now they all come without the cap gasket.
The cap screws on or off tight seal in 3 turns or less
Attachments
Jewels
Bon~Fire
Yes.
Yes.
Those two questions do not have a directly proportional relationship.
A word about pumps.
There are essentially two styles of pumps we will see in this application. Depending on the pitch of the prop, the pump may be considered a volume pump or a pressure pump.
Understand, props do not spin willynilly like an electric hand mixer whiping an egg.
You have to imagine the prop moving through water, like a screw, turning through wood. It is the pitch of the threads that determines how far to screw travels through the wood with each revolution.
A volume pump has an aggressive pitch, it moves more water per revolution. This style of pump operates with low torque -output diminishes exponentially with resistance or head.
A pressure pump has a comparatively flat pitch. It may not be advertising the same volume as a flow pump, but it has torque and the ability to overcome resistance without significantly diminishing flow.
Any quality pump will come with a graph showing the pumps capabilities at a given head.
Plain English?
Your pump manufacturer will lie and lie and lie all day long.
Buy the biggest pump you can afford , You can always install a relief loop.
NEVER restrict intake, the pump gets hot and output is reduced to a trickle.
I challenge anyone with one of these systems to actually measure the volume of water that is RETURNED by the pump.
Spoiler alert : it is not the number printed on the side of the box.
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BubblySeeder
New Member
Couple questions... as I'm buying parts for my first RDWC build.
Has anyone experienced a blockage that caused a bucket to overflow? I'm wondering if that is an issue for me to worry about.
2nd question. I'm not planning to use a water chiller or a top off res right away. Likely add them at some point after a few grows, but is there any benefit for making the Epi bucket be slightly larger? Say the 5 gallon square uline bucket vs the 4 gallon. I'm thinking the added size might help during flush/refill.
Has anyone experienced a blockage that caused a bucket to overflow? I'm wondering if that is an issue for me to worry about.
2nd question. I'm not planning to use a water chiller or a top off res right away. Likely add them at some point after a few grows, but is there any benefit for making the Epi bucket be slightly larger? Say the 5 gallon square uline bucket vs the 4 gallon. I'm thinking the added size might help during flush/refill.
Armdog
RDWC GROWER
I read somewhere it is between 30% to 50% less than advertised. They test their pumps with 0 head height. So depending on how high or long you are pumping affects your pumps output. Just my 2 cents.
Jewels
Bon~Fire
Could be anything ,really.
Most of you guys are running a closed loop system , where water is drawn and returned from the same level. Theoreticaly, this is zero head.
Consider the fine print from Venta-hood.
,,,Paraphrasing -,,, " this ventilation system is designed and engineered for a 10-foot exhaust duct. Every 90 degree elbow will subtract an equivalent of 3 feet. "
So, two elbows later and this fan wont make it to the end of my kitchen counter.
Perhaps apples and oranges, but 4 elbows later and this system has zero output.
How many elbows are in your system?
Most of you guys are running a closed loop system , where water is drawn and returned from the same level. Theoreticaly, this is zero head.
Consider the fine print from Venta-hood.
,,,Paraphrasing -,,, " this ventilation system is designed and engineered for a 10-foot exhaust duct. Every 90 degree elbow will subtract an equivalent of 3 feet. "
So, two elbows later and this fan wont make it to the end of my kitchen counter.
Perhaps apples and oranges, but 4 elbows later and this system has zero output.
How many elbows are in your system?
BubblySeeder
New Member
I'm planing to put my upcoming build in small grow tent. 4 buckets and an Epi outside the grow tent. I'm thinking a single 2" line from Epi to a tee inside with reducers to 1.5" going to both sides. Here is a small diagram (not to scale) of what I'm considering building. No chiller or anything fancy at the moment, but wanting to preserve as much of the original Heisen proven design as possible so someday I can expand and re-use what I have here. Reason for 2" line is I want to fit piping thru a small opening in tent wall.
Any recommendations from this group before I start purchasing and building?
Any recommendations from this group before I start purchasing and building?
I dont see the advantage of an undercurrent system vs a regular rdwc. What makes the system better for water to fly through the buckets and around through epi at lightning speeds vs slowly moving the water in a normal rdwc or slowly in an UC system? Other than waiting a little longer to ck your pH or ppms when adjusting, the slower moving system should keep everything equalized as far as pH,ppms,water temps. Maybe even cooler water temps with a smaller pump and without that strong current the roots want be as likely to clog pipes. The waterfall coming back into the epi breaking surface tension may aid in aeration but for the most part the air pumps add just as much aeration in either system. General hydroponics had problems with there 8 pk waterfarm system with unequal pH and ppms until they added the xtra pumping column and made it a recirculating system, but I think we've all seen how slow those columns are at pumping water and those systems work good at keeping everything stabilized throughout the system, given you do have to wait all day to ck the solution when making adjustments. I do love the undercurrent systems and I think they just look cool as hell with the big pipe and all but are they really all that better vs a regular rdwc? Why?
Jewels
Bon~Fire
Jewels personal rdwc Theory-
No one would expect to live very long with a plastic bag tied around their head.
In a room with dead air, a leaf surface will rapidly consume all the available nutrients (CO2) . A stagnant film will coat the leaf surface, and photosynthesis suffers.
Growers have long known to add a fan to encourage constant exchanges. Also, we have learned to provide a supply of fresh air to equalibriate and replenish.
Same thing with oxygen @ the root zone.
Imagine a red in colour, zero buoyancy ball, flotsaming around the hydroponic circuit. Everytime the ball happens to touch a root, the ball turns blue, and continues on it's journey.
The only way for that spent ( de-oxygenated) blue ball to become replenished and red (oxygenated) is to come in contact with the water surface.
In a slow system that blue ball may need hours to broach the surface, before it becomes red again. How long will it take that now red ball to come in contact with the root surface again ?
Do you want these exchanges to occur by coincidence, every few hours, or do you want them happening in reliable, rapid succession ?
What if the same system had twice the previous surface area?
Would the ball not reach the surface twice as often?
What if I doubled the rate of flow? With those two tweeks, is my system now four times as efficient?
Am I making sense ?
The same thing is true of circulated nutrients.
A film of nutrient-poor water can accumulate on the root surface.
Eventually homeostasis may even things out, but we do not have that kind of time.
Put a drop of purple food colouring into a 5 gallon bucket full of dirt. As you water the pot a few times a week, after a few months or so the entire contents of the bucket will be dyed purple.
Can a PH measurement ever be accurate in a slow-moving system?
I want purple right now.
Using this logic there must be an upper limit. If I hyperventilate I do not become superhuman. There is not enough dwell time on my alveoli's surface area to successfully extract oxygen. This phenomenan also holds true with the nitrifying bacteria and a aquatic system fish filter. It needs contact time to successfully make the N. exchanges. If everything blows by too quickly- it just will not happen. I am sure this scenario could exist in a hydroponic system; although I do not believe any of us are pushing enough water to come anywhere near that possiblity.
No one would expect to live very long with a plastic bag tied around their head.
In a room with dead air, a leaf surface will rapidly consume all the available nutrients (CO2) . A stagnant film will coat the leaf surface, and photosynthesis suffers.
Growers have long known to add a fan to encourage constant exchanges. Also, we have learned to provide a supply of fresh air to equalibriate and replenish.
Same thing with oxygen @ the root zone.
Imagine a red in colour, zero buoyancy ball, flotsaming around the hydroponic circuit. Everytime the ball happens to touch a root, the ball turns blue, and continues on it's journey.
The only way for that spent ( de-oxygenated) blue ball to become replenished and red (oxygenated) is to come in contact with the water surface.
In a slow system that blue ball may need hours to broach the surface, before it becomes red again. How long will it take that now red ball to come in contact with the root surface again ?
Do you want these exchanges to occur by coincidence, every few hours, or do you want them happening in reliable, rapid succession ?
What if the same system had twice the previous surface area?
Would the ball not reach the surface twice as often?
What if I doubled the rate of flow? With those two tweeks, is my system now four times as efficient?
Am I making sense ?
The same thing is true of circulated nutrients.
A film of nutrient-poor water can accumulate on the root surface.
Eventually homeostasis may even things out, but we do not have that kind of time.
Put a drop of purple food colouring into a 5 gallon bucket full of dirt. As you water the pot a few times a week, after a few months or so the entire contents of the bucket will be dyed purple.
Can a PH measurement ever be accurate in a slow-moving system?
I want purple right now.
Using this logic there must be an upper limit. If I hyperventilate I do not become superhuman. There is not enough dwell time on my alveoli's surface area to successfully extract oxygen. This phenomenan also holds true with the nitrifying bacteria and a aquatic system fish filter. It needs contact time to successfully make the N. exchanges. If everything blows by too quickly- it just will not happen. I am sure this scenario could exist in a hydroponic system; although I do not believe any of us are pushing enough water to come anywhere near that possiblity.
I'm just not sure that there would be that much more surface tension broke in an undercurrent system vs a slower moving rdwc. The reason being most of the flow is near the bottom of the bucket and once it fills up with roots it may be worse. Without scientific studies it's hard to say there would be that much more than just having both systems highly aerated with good air pumps and micro pores stones. I'm sure there may be a little more because theres more action going on but is it enough to offset the trouble with root clogging and maybe higher temps with a bigger pump. As far pH I wouldnt think there would be any variation within the system using a 250gph vs 1000gph just the speed of the initial mixing. Of course this is all opinion on my part. Personally I like the undercurrent setup better, just like the layout better but I want to experiment with a slower current to avoid clogging. The performance of both systems seems pretty close from what little I can find with the same size containers throughout the system. Good analogy on the red/blue dot.
Jewels
Bon~Fire
I totaly agree, both of those systems are going to give you blue balls, everytime.
Roots can strip oxygen off roots very quickly. That would be my best answer for over circulating.
I really enjoy your critical thinking.
There will never be a catch all answer. Always trade offs.
Air pumps consume power and add costs, noise and heat.
Microstones clog up.
I am not certain what makes some roots grow longer than others.
The root theory of constant circulation holds true. Any unruly mass of roots is difficult to penetrate with a supply of replenished water. There will be an incredible difference in measurements in the epi vs. a rotting snotglobberish muckroot. A sterile system is not equiped to manage that scenario.
By pushing through a ridiculous amount of water, those dead spots are diminished.
You have identified ways that roots become anaerobic, so the key would be to avoid that.
Find ways that will constantly circulate replenished water around the roots, and you are golden.
Roots can strip oxygen off roots very quickly. That would be my best answer for over circulating.
I really enjoy your critical thinking.
There will never be a catch all answer. Always trade offs.
Air pumps consume power and add costs, noise and heat.
Microstones clog up.
I am not certain what makes some roots grow longer than others.
The root theory of constant circulation holds true. Any unruly mass of roots is difficult to penetrate with a supply of replenished water. There will be an incredible difference in measurements in the epi vs. a rotting snotglobberish muckroot. A sterile system is not equiped to manage that scenario.
By pushing through a ridiculous amount of water, those dead spots are diminished.
You have identified ways that roots become anaerobic, so the key would be to avoid that.
Find ways that will constantly circulate replenished water around the roots, and you are golden.
I've noticed some plants have extremely long roots while other plants have really short roots, I had a Black Russian from delicious seeds that the roots never got over about a ft to 1-1/2 ft long, wish I had it back would be perfect for one of these systems and was a nice plant to boot.
I guess I've been lucky to avoid the anaerobic scenario, even back when I used the water farm system from GH before they revised it to circulate but I've always been big on lots of air/huge air pumps and cold water. Plus I guess I have pretty good water also, I haven't noticed a difference between using my tap and RO, and water quality plays a big role in these systems. I've always believed good cool water and a super highly oxygenated root zone is key to any dwc system. Another thing to take into consideration with a slower pump vs big pump when it's been run for a while, the small pump may be moving just as much water throughout the system as the larger pump if the larger pump and current has carried a root mass into the pipes and reduced flow. To many factors to take into consideration to form a solid opinion on theory alone. I need to see actual results and a good side by side with the same system and genetics/environment with the only difference being the water pumps is really the only way to say positively one way or the other. I do believe one answer to these systems lies in beneficial organisms to feed on these problems as they arise. Experimenting and trial an error will find the answers.
Peace!
I guess I've been lucky to avoid the anaerobic scenario, even back when I used the water farm system from GH before they revised it to circulate but I've always been big on lots of air/huge air pumps and cold water. Plus I guess I have pretty good water also, I haven't noticed a difference between using my tap and RO, and water quality plays a big role in these systems. I've always believed good cool water and a super highly oxygenated root zone is key to any dwc system. Another thing to take into consideration with a slower pump vs big pump when it's been run for a while, the small pump may be moving just as much water throughout the system as the larger pump if the larger pump and current has carried a root mass into the pipes and reduced flow. To many factors to take into consideration to form a solid opinion on theory alone. I need to see actual results and a good side by side with the same system and genetics/environment with the only difference being the water pumps is really the only way to say positively one way or the other. I do believe one answer to these systems lies in beneficial organisms to feed on these problems as they arise. Experimenting and trial an error will find the answers.
Peace!
Id use a larger epi if your not connecting a top off because when these plants get big they can suck down a lot of solution in a day, a big plant can drink 1 to 2 gallons a day. And yes roots can clog and cause problems, always pay attention to the exit pipe in each bucket and monitor/ trim roots, whatever you have to do to keep from clogging. The majority of the time if they do grow into the pipes they dont create a large enough mass to restrict flow but some plants/strains are different. The one time you dont keep an eye on it, monitor it, things will clog up and create problems and you may end up with a bunch of solution on the floor.
Also wanted to add, couldn't tell by your diagram, but I like to have a mesh filter right before the ball valve just in case any roots or debris/small pieces of hydroton make it's way to the pump.
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Thanks all! Armdog... I’ll definitely look into the Al40 air pump. Sounds like exactly what I need.
Jewels/boy blue...thanks much for your guidance. I’m an experienced soil scrog grower but this will be my first rdwc grow so please forgive my ignorance. I’m not really sure how to identify a volume pump vs a pressure pump... and even if I do...which is best for this application?
As a newbie... can you guys recommend a few make/model for water pump that would be ideal for a 5 (4 gal) pot system? Noise is not an issue and I I’m willing to spend a little extra for a superior solution.
Jewels.... I loved to red/blue dot analogy as well. Please keep the knowledge coming!
Jewels/boy blue...thanks much for your guidance. I’m an experienced soil scrog grower but this will be my first rdwc grow so please forgive my ignorance. I’m not really sure how to identify a volume pump vs a pressure pump... and even if I do...which is best for this application?
As a newbie... can you guys recommend a few make/model for water pump that would be ideal for a 5 (4 gal) pot system? Noise is not an issue and I I’m willing to spend a little extra for a superior solution.
Jewels.... I loved to red/blue dot analogy as well. Please keep the knowledge coming!
Armdog
RDWC GROWER
Thanks for the video Heisen
Armdog
RDWC GROWER
I use a active aqua Submersible pump 400. 370 gph. Works great for 5 buckets.Thanks all! Armdog... I’ll definitely look into the Al40 air pump. Sounds like exactly what I need.
Jewels/boy blue...thanks much for your guidance. I’m an experienced soil scrog grower but this will be my first rdwc grow so please forgive my ignorance. I’m not really sure how to identify a volume pump vs a pressure pump... and even if I do...which is best for this application?
As a newbie... can you guys recommend a few make/model for water pump that would be ideal for a 5 (4 gal) pot system? Noise is not an issue and I I’m willing to spend a little extra for a superior solution.
Jewels.... I loved to red/blue dot analogy as well. Please keep the knowledge coming!