URDWC what size pump?
- Thread starter macsnax
- Start date
JSB99
Well-Known Member
Consider using 27-gallon HDX totes, to hold two plants each, instead of buckets. You'll be able to have way more water in your system, and much more room for roots in the totes. Using the actual amount of water you'd probably have in your containers, you'd be looking at 160 total gallons, with the totes, compared to just 56 total gallons, with buckets. This doesn't include the controller reservoir or pipes, just the plant containers.
8 x 27-gallon totes, holding 20-gallons each =160 total gallons
16 x 5-gallon buckets, holding 3.5-gallons each = 56 total gallons
Also, if you're doing a system that big, and with UC in general, you want BIG pipes! I wouldn't go any smaller than 2". With pipes that big, you're going to have a difficult time mounting them to round surfaces. Flat surfaces are definitely recommended for bulkheads this big.
You could save a ton of money building your own, if you're handy and can learn how to do basic PVC tutorials on YouTube. You can use the money you saved on better pumps and lights. RDWC/UC is pretty easy to work with.
Check out my RDWC link below. I started off with buckets, then switched to totes mid-build. If you skip to page 30 and 31, you can see much more recent pics.
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JSB99
Well-Known Member
To answer your initial question, with under current, you want to be able to cycle the total gallons in the system, 12 times an hour. So, a 100-gallon system would need a 1200gph pump.
For each 8-site + 1-reservoir bucket system, holding approximately 34 total gallons, you'd need at least a 400gph pump.
If you opt for the larger totes, and you still want to have two separate systems, you'd be using 5 totes for each (4 plant totes, and 1 tote as the reservoir for each system). That'd be about 100-gallons each, which would be a 1200gph pump, same as the example above. If you want to use all the totes in a single system, you'd be using 9-totes, and holding 180 total gallons. For that, you'd want a 2200gph pump. It's always better to go bigger on your pump, so those values are the minimum.
If you plan on using an air pump, along with a water pump, then you can just run an RDWC, instead of Under Current, because you are increasing the ability of dissolved oxygen to get to the inner roots. That means you don't have to go as big on your water pump. It also adds redundancy. If either your water pump or air pump dies, the remaining pump will keep things alive until you get a replacement.
For each 8-site + 1-reservoir bucket system, holding approximately 34 total gallons, you'd need at least a 400gph pump.
If you opt for the larger totes, and you still want to have two separate systems, you'd be using 5 totes for each (4 plant totes, and 1 tote as the reservoir for each system). That'd be about 100-gallons each, which would be a 1200gph pump, same as the example above. If you want to use all the totes in a single system, you'd be using 9-totes, and holding 180 total gallons. For that, you'd want a 2200gph pump. It's always better to go bigger on your pump, so those values are the minimum.
If you plan on using an air pump, along with a water pump, then you can just run an RDWC, instead of Under Current, because you are increasing the ability of dissolved oxygen to get to the inner roots. That means you don't have to go as big on your water pump. It also adds redundancy. If either your water pump or air pump dies, the remaining pump will keep things alive until you get a replacement.
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macsnax
Well-Known Member
I was thinking there might be flow issues using 5 gal buckets once the root mass becomes larger. I like those 27 gal totes. Honestly I'm open to ideas too. I'm still trying to figure out the plumbing. I'm thinking 2" pvc. Pump between res and buckets and a ball valve on the return? Not sure what size the return line should be..... Not sure if I need a water chiller with the larger totes..... Sorry it took so long to reply. I've been reading a lot, the undercurrent in the 27 gal sounds great. Lots of room for roots, and I really don't want to run air pumps. Maybe have a couple on hand for backup though. Feel free to kick some ideas around, this is my first venture into hydro.
One more thing, is there any issues with the lids being yellow? Light getting through? The more I think about using those totes I see more pros than cons.
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JSB99
Well-Known Member
I wanted to mention that I am in no way, the first to come up with the HDX tote idea. Several people have done this, and it was advised to me, as I was building my system. I'm just forwarding some very helpful information 
My manifolds. I have six valves here. This is where my controller reservoir sits. It stays way cooler outside the tent:
These were yellow, before I painted them with PlastiDip grey:
A few solutions:
This is when I used the extra Hydroton I had, to cover the lid. It worked really well, but was a little bit of a pain when it came time to clean everything up, after the grow:
Definitely. The purpose of using a powerful pump is so there's enough force to get DO to the center of the roots. You might be able to get some through the first bucket or two, but after that, I doubt there'd be enough force left.
As mentioned, I wouldn't go with anything smaller than 2". With your setup, I would be looking at 3" or 4". The price does go up, with the increase in pipe size, but you want as little flow restrictions as possible. Plus, it really helps prevent root clogging.
Simply put, yes. However, you are going to want more functionality with your valves. You're going to want a way to drain your system, using the pump you already have. You might want a bleed-valve, where you can prevent bubbles from going through your pump, and blow out leftover water when you want to remove the pump. I know that sounds a little confusing, but I can explain it using my own pump in and out manifolds if you don't get it. Valves give you great versatility with a single pump.
My manifolds. I have six valves here. This is where my controller reservoir sits. It stays way cooler outside the tent:
3/4" to 1" should be fine. Poly vinyl tubing works well for this. I'm using 2" pipes for the UC manifolds, and 3/4" poly tubing to the pump's input manifold:
Depends on a lot. Are you going to have the reservoirs in the same area as your lights? I keep mine outside my tent. The room is around 68, and my reservoir stays there as well. I have a small fan blowing on the surface of the reservoir water. This is "evaporative cooling", and works really well for cheaply shaving 5 to 10 degrees off. Also, if you keep a fan blowing on your pump, it'll really help keep the temps down.
Yep, there sure is. Those yellow lids bleed through bad!
These were yellow, before I painted them with PlastiDip grey:
A few solutions:
- Paint the lids with PlastiDip spray paint, or primer
- Cut a piece of wood in the shape of the inner-lids, and cover with that
- Cut up a pond liner, or some other thick plastic sheeting
- Pour Hydroton a few inches thick, on the lid
This is when I used the extra Hydroton I had, to cover the lid. It worked really well, but was a little bit of a pain when it came time to clean everything up, after the grow:
Nothing to worry about. Glad to hear you're researching! Practice the "six P''s"... Proper Planning Prevents Piss Poor Performance
Cold$moke
Well-Known Member
Make an emphasis when reading to look up rdwc failures
This will help you avoid problems.
JSB99 has you pretty lined out
I only have one issue with uc style systems
I theorize that when having a system that pulls out of every tote from the bottom
The last totes in the system would be pulling less then the fronts .
No exp from use though
I built my rdwc set up differently
macsnax
Well-Known Member
Yeah I've seen those yellows lids a few times now while doing research....Please do explain about how your valves are setup..... I've been taking in a ton of information and I would rather do this right the first time..... I think I'm going to have my reservoirs outside my tents, I'm still considering the best way to put a round hole in the tent material.....plastiDip so many uses......thanks for all the comments, keep them coming and don't let me do anything stupid. I think I have a decent plan, I'm going to keep doing research and making a list that I will post so I can get some input if there are better options or if I'm over/under doing things.I wanted to mention that I am in no way, the first to come up with the HDX tote idea. Several people have done this, and it was advised to me, as I was building my system. I'm just forwarding some very helpful information
Definitely. The purpose of using a powerful pump is so there's enough force to get DO to the center of the roots. You might be able to get some through the first bucket or two, but after that, I doubt there'd be enough force left.
As mentioned, I wouldn't go with anything smaller than 2". With your setup, I would be looking at 3" or 4". The price does go up, with the increase in pipe size, but you want as little flow restrictions as possible. Plus, it really helps prevent root clogging.
Simply put, yes. However, you are going to want more functionality with your valves. You're going to want a way to drain your system, using the pump you already have. You might want a bleed-valve, where you can prevent bubbles from going through your pump, and blow out leftover water when you want to remove the pump. I know that sounds a little confusing, but I can explain it using my own pump in and out manifolds if you don't get it. Valves give you great versatility with a single pump.
My manifolds. I have six valves here. This is where my controller reservoir sits. It stays way cooler outside the tent:
3/4" to 1" should be fine. Poly vinyl tubing works well for this. I'm using 2" pipes for the UC manifolds, and 3/4" poly tubing to the pump's input manifold:
Depends on a lot. Are you going to have the reservoirs in the same area as your lights? I keep mine outside my tent. The room is around 68, and my reservoir stays there as well. I have a small fan blowing on the surface of the reservoir water. This is "evaporative cooling", and works really well for cheaply shaving 5 to 10 degrees off. Also, if you keep a fan blowing on your pump, it'll really help keep the temps down.
Yep, there sure is. Those yellow lids bleed through bad!
These were yellow, before I painted them with PlastiDip grey:
A few solutions:
- Paint the lids with PlastiDip spray paint, or primer
- Cut a piece of wood in the shape of the inner-lids, and cover with that
- Cut up a pond liner, or some other thick plastic sheeting
- Pour Hydroton a few inches thick, on the lid
This is when I used the extra Hydroton I had, to cover the lid. It worked really well, but was a little bit of a pain when it came time to clean everything up, after the grow:
Nothing to worry about. Glad to hear you're researching! Practice the "six P''s"... Proper Planning Prevents Piss Poor Performance
macsnax
Well-Known Member
Not a bad idea to look at others mistakes and be ahead of the curve.Make an emphasis when reading to look up rdwc failures
This will help you avoid problems.
JSB99 has you pretty lined out
I only have one issue with uc style systems
I theorize that when having a system that pulls out of every tote from the bottom
The last totes in the system would be pulling less then the fronts .
No exp from use though
I built my rdwc set up differently
Cold$moke
Well-Known Member
Its what i did! ha ha
I havent seen anyones rdwc quite like mine
But i did that on purpose all outside the box lol
Whether or not its worth it is yet to be seen ill know in 8to 10 weeks
macsnax
Well-Known Member
Nice, let us know how it goes.Its what i did! ha ha
I havent seen anyones rdwc quite like mine
But i did that on purpose all outside the box lol
Whether or not its worth it is yet to be seen ill know in 8to 10 weeks
JSB99
Well-Known Member
You asked for it LOL!
1 - Water Return Line - This is where the 3/4" black poly tubing, from the tent, connects. The tube isn't connected in this picture though.
2 - Input Manifold Valve - This controls the water from the entire system. Closing this allows everything after it to be disassembled. This is really useful for taking the pump out to clean, or replace.
3 - Bleed Valve - This serves two purposes. One, after closing the Input Manifold Valve (2), all the pipes after still have water, which will spill out if anything is taken apart. Opening this valve allows me to blow out the remaining water, in the pipes and pump. And two, After opening the Input Manifold Valve (2), air gets trapped in the 3/4" return line, and the input manifold. The air has to then work its way out through the pump and pipes, which makes the pump sputter for a bit. Opening the valve allows me to bleed any trapped air. This results in the pump being full force, as soon as it's plugged in.
4 - Waterfall Valve - Used in conjunction with the Drain Valve (5) to either route the water to the waterfall, or to the drain pipe going through the wall to the outside.
5 - Drain Valve - (explained above)
6 - House Water Valve - I tapped into one of the house water pipes to be able to fill the system.
7 - Reservoir Valve - I have a 55-gallon reservoir, where I can bubble out chlorine (yes, my water only has chlorine, not chloramine). This valve allows me to fill the system from the reservoir. I can also drain the reservoir, if I ever needed, by routing the water out the drain pipe instead of the waterfall.
8 & 9 - Pump Input & Output Unions - Using these allow for very easy mounting and removal of the pump, without any moving pipes. I'm not using an inline filter right now, so being able to quickly remove the pump for cleaning each week keeps everything running smooth. Only takes a minute or two to clean the pump.
10 - Waterfall - This is just a length of 1/2" PVC with small holes drilled through it (which you can't see here). This creates pressure, and jets the water out, which creates a ton of DO in the reservoir. The pipe, adapter, and end cap are not glued or screwed together. There's not enough pressure to separate them. This allows for easy removal to clean it, and even replace it with another pipe, with different holes drilled into it.
11 - 2" Feed Pipe - This is where the flow starts. This goes from the controller reservoir, through the back of the tent to the UC Input Manifold, then through the totes to the UC Output Manifold, to the 3/4" black tubing, and into the Pump Input Manifold (1)
This is with my controller reservoir in place:
I use this fan, I wall-mounted, to blow on the pump to keep it cool, as well as blow on the reservoir water to help keep it cool via evaporative cooling. You have to have the lid off to do this, so it's really important to have your res in a dark spot to prevent algae growth. With the combination of having the res outside the tent, cooling the pumps, and cooling the water a little, keeps my temps between 66 and 68:
As far as passing pipes through the back of the tent, it's easy! I'm sure a lot of people have reservations about cutting their tent, but the tents are cheap and don't retain any value, so it's not like there's a huge market for used grow tents. The benefits to having the reservoir outside the tent, are great! You're going to have much more room in the tent for plants, you're removing the reservoir from a warm area, which helps with the water temps, and it gives you much easier access to the reservoir, as you don't need to open the tent to get to it.
Blurry pic of the UC input manifold, air pump manifold, and black poly return tube, passing through the tent. All you have to do is slice the tent a little, where you need to pass something through, and use a little duct tape to cover any over-cuts. I use a 2" rubber coupling to join the pipe that comes into the tent, to the UC input manifold. This allows for very easily connecting/disconnecting the manifold for cleaning. Wanted to also mention that the reason I use a long curve, with regards to the black tube, is because this tube is where you can run into bottlenecks. Instead of going straight through the back of the tent, and using a 90 degree elbow and running another tube to the pump input manifold, I use a single, gently curved tube, with no adapters. Doing this resulted in significant increase in flow.
Hope all that helps you out
macsnax
Well-Known Member
Wow, that's a lot to take in. I think I'm going to go with the hdx totes, 4 totes per system including res (one for veg, one for flower) 12 plants total. I can always expand of I want. 1000 gph pumps should recalculate 14. something times per hour at 20 gallons per tote. I should be getting most of this stuff in the next week. When it comes time to plumb everything I'm going to have questions. You've been a big help, I hope you don't mind if I ask for advice on plumbing during the build. Thanks manYou asked for it LOL!
View attachment 4098448
1 - Water Return Line - This is where the 3/4" black poly tubing, from the tent, connects. The tube isn't connected in this picture though.
2 - Input Manifold Valve - This controls the water from the entire system. Closing this allows everything after it to be disassembled. This is really useful for taking the pump out to clean, or replace.
3 - Bleed Valve - This serves two purposes. One, after closing the Input Manifold Valve (2), all the pipes after still have water, which will spill out if anything is taken apart. Opening this valve allows me to blow out the remaining water, in the pipes and pump. And two, After opening the Input Manifold Valve (2), air gets trapped in the 3/4" return line, and the input manifold. The air has to then work its way out through the pump and pipes, which makes the pump sputter for a bit. Opening the valve allows me to bleed any trapped air. This results in the pump being full force, as soon as it's plugged in.
4 - Waterfall Valve - Used in conjunction with the Drain Valve (5) to either route the water to the waterfall, or to the drain pipe going through the wall to the outside.
5 - Drain Valve - (explained above)
6 - House Water Valve - I tapped into one of the house water pipes to be able to fill the system.
7 - Reservoir Valve - I have a 55-gallon reservoir, where I can bubble out chlorine (yes, my water only has chlorine, not chloramine). This valve allows me to fill the system from the reservoir. I can also drain the reservoir, if I ever needed, by routing the water out the drain pipe instead of the waterfall.
8 & 9 - Pump Input & Output Unions - Using these allow for very easy mounting and removal of the pump, without any moving pipes. I'm not using an inline filter right now, so being able to quickly remove the pump for cleaning each week keeps everything running smooth. Only takes a minute or two to clean the pump.
10 - Waterfall - This is just a length of 1/2" PVC with small holes drilled through it (which you can't see here). This creates pressure, and jets the water out, which creates a ton of DO in the reservoir. The pipe, adapter, and end cap are not glued or screwed together. There's not enough pressure to separate them. This allows for easy removal to clean it, and even replace it with another pipe, with different holes drilled into it.
11 - 2" Feed Pipe - This is where the flow starts. This goes from the controller reservoir, through the back of the tent to the UC Input Manifold, then through the totes to the UC Output Manifold, to the 3/4" black tubing, and into the Pump Input Manifold (1)
This is with my controller reservoir in place:
View attachment 4098472
I use this fan, I wall-mounted, to blow on the pump to keep it cool, as well as blow on the reservoir water to help keep it cool via evaporative cooling. You have to have the lid off to do this, so it's really important to have your res in a dark spot to prevent algae growth. With the combination of having the res outside the tent, cooling the pumps, and cooling the water a little, keeps my temps between 66 and 68:
View attachment 4098473
As far as passing pipes through the back of the tent, it's easy! I'm sure a lot of people have reservations about cutting their tent, but the tents are cheap and don't retain any value, so it's not like there's a huge market for used grow tents. The benefits to having the reservoir outside the tent, are great! You're going to have much more room in the tent for plants, you're removing the reservoir from a warm area, which helps with the water temps, and it gives you much easier access to the reservoir, as you don't need to open the tent to get to it.
Blurry pic of the UC input manifold, air pump manifold, and black poly return tube, passing through the tent. All you have to do is slice the tent a little, where you need to pass something through, and use a little duct tape to cover any over-cuts. I use a 2" rubber coupling to join the pipe that comes into the tent, to the UC input manifold. This allows for very easily connecting/disconnecting the manifold for cleaning. Wanted to also mention that the reason I use a long curve, with regards to the black tube, is because this tube is where you can run into bottlenecks. Instead of going straight through the back of the tent, and using a 90 degree elbow and running another tube to the pump input manifold, I use a single, gently curved tube, with no adapters. Doing this resulted in significant increase in flow.
Hope all that helps you out
SmokeyMcChokey
Well-Known Member
Wouldn't you need airstones with undercurrent as it's not waterfalling or fluming?
JSB99
Well-Known Member
No problemWow, that's a lot to take in. I think I'm going to go with the hdx totes, 4 totes per system including res (one for veg, one for flower) 12 plants total. I can always expand of I want. 1000 gph pumps should recalculate 14. something times per hour at 20 gallons per tote. I should be getting most of this stuff in the next week. When it comes time to plumb everything I'm going to have questions. You've been a big help, I hope you don't mind if I ask for advice on plumbing during the build. Thanks man
.Glad I could help spread the knowledge that I have gathered myself, along the way.Oversizing your pumps is a good idea, with UC, but I think there's a trade-off once you go really oversized. You'll be fighting extra heat from the pump, it's going to consume more power, and the pumps are going to cost more, both the purchase, and replace. But you'll have to figure out where that line is. I've got to get a larger pump, if I want to qualify it as an true UC. My original design, using buckets, held much less water, and is what I based my original pump on. I almost tripled the amount of water, so my system is really an RDWC, as I'm only circulating the water around five or six times an hour. But, I'm providing a lot of DO with my airstones, so it's okay. Because there's a maximum amount of dissolved oxygen plants can use (as tested by @Cold$moke), I doubt I would be proving any more DO the roots would be able to use, by going to a bigger pump.
Canadain Closet Gardener
Well-Known Member
I think totes are better too because the fittings fit better than on buckets
I'm planning on building on of those systems on my balcony to grow tomatoes. I'm waiting for my 3" Current Culture bulkheads to arrive.
Cheers
CCG
I'm planning on building on of those systems on my balcony to grow tomatoes. I'm waiting for my 3" Current Culture bulkheads to arrive.
Cheers
CCG
Cold$moke
Well-Known Member
He waterfalls and flums his res i think
Cold$moke
Well-Known Member
You can make it work with round stuff.
Remember guys uni seals where invented to tie in plumbing to other plumbing (both are round
)Most peeps just cant drill a hole cleanly or accurately enough .
They work fine although yes flat makes it easier
Cold$moke
Well-Known Member
No problem
Oversizing your pumps is a good idea, with UC, but I think there's a trade-off once you go really oversized. You'll be fighting extra heat from the pump, it's going to consume more power, and the pumps are going to cost more, both the purchase, and replace. But you'll have to figure out where that line is. I've got to get a larger pump, if I want to qualify it as an true UC. My original design, using buckets, held much less water, and is what I based my original pump on. I almost tripled the amount of water, so my system is really an RDWC, as I'm only circulating the water around five or six times an hour. But, I'm providing a lot of DO with my airstones, so it's okay. Because there's a maximum amount of dissolved oxygen plants can use (as tested by @Cold$moke), I doubt I would be proving any more DO the roots would be able to use, by going to a bigger pump.
He he wasnt my post
Just had such good info i saved it.
I pull it out for peeps that think stones are better then surface disruption for DO
(But stones do have specific jobs)
SmokeyMcChokey
Well-Known Member
And that's enough? I'm finishing my clean out and setup Sunday and kinda wanna either get a commercial air pump. But hate the heat possibility, noise doesn't really matter to me unless it's over 70 ish db. But I'd rather just airstone my res and let the pump do the rest. I'm doing I think like 1/4" elbows forfmy feed lines so it's probably not adequate to disturb enough water in each tote. That's my concern at least. I'm also only doing I think k about 500 gph for water pump after head loss so that may not be quite enough too. Rather not go any bigger for heat concerns too. Summer is coming fast.