need help visualizing the MPB setup

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Papa

Papa

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That's because DD went to another forum. He explains it a little better, He moves the drain to the bottom and feeds from the top. I'm not allowed to link but google it. I would never have my drain on the same level as the feed unless i was nft or swc.

i'm getting a bit more confused about this.

regarding the bucket in the "10 lb test" . . . . he says (@ that other site, in part):

what you see hear is basically an undercurrent but i souped it up. room is 7ft tall hence the undercurrent style to keep the plant res's on the floor, not raised as mpb style. dds

but my original point remains the same . . . i don't see how you can achieve a bottom drain and feed at the top . . . . unless you are bringing the drainpipe back up (outside of the bucket) and create a weir. i've stared at that interior bucket pic quite a few times, and see only the two white bulkhead fittings and that yellow thingy. they all seem to be at the same level. do you see another down lower? if it works like a UC, then one of the white would be an inlet and the other an outlet . . . but they seem small for the flow that i assume he would use. are there other pics that show what's going on?
 
T

tedsprogz

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look at that picture of the inside. the 2 white bulkheads are close to the bottom(you can confirm by looking at the pic above it). The feed is the yellow thing only an inch from the rim. But yea i had to bend my brain to finally get it. I'm thinking what I'm explaining is in the thread that used to be in the sticky... the one that had the parts list and all the broken pics.
 
joehank

joehank

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Feeding from the lid you would think that it would be hard to keep your water level at the perfect level

I think that as long as the drains are still on the side up high, then it should be fine. It is still going to fill up until it hits the drain I would imagine.
 
Capulator

Capulator

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from what I remember seeing he just moved the top feed up above the drains. That makes sense since then you dont need a check valve.
 
D

Drdre

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Also keep in mind that your roots are suspended in water once you fill your tubs out the force of your feed could damange your roots. Thompsons had plugs I bought for the bottom of the tubs that disperse the water flat and evenly
 
Papa

Papa

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look at that picture of the inside. the 2 white bulkheads are close to the bottom(you can confirm by looking at the pic above it). The feed is the yellow thing only an inch from the rim. But yea i had to bend my brain to finally get it. I'm thinking what I'm explaining is in the thread that used to be in the sticky... the one that had the parts list and all the broken pics.

but to clarify . . . . these big tubs that dds used in the 10 lb. test are not mpbs. this is what was not clear to me until i read dds statement that they're "basically an undercurrent but i souped it up."

in an mpb, each tub independently drains directly back to the rez . . . there is an air break (a plumbing term) in the drain. in these tubs dds used for the 10 lb test . . . a modified UC-type design, there is no air break . . . these white bulkheads would be used to connect one tub to another, and to a rez that all maintained the same water level. (one of the defining differences between an mpb-type design and a UC-type design is that in an mpb the water level is lower in the rez than in the buckets . . . in a UC-type design the water level is the same)

that feed in each bucket, however, would be a difference from what UC does. it would push the water from the rez out to the buckets instead of suck it back to the rez from the buckets. i love that there are so many different ways to successfully accomplish dwc.
 
J

Jalisco Kid

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This is a system I do not use, but I would think your intake above the drains will limit your girls to the amount of food/air they can take in. Suerte JK
 
joehank

joehank

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I have not seen this system in operation so I don't know the force of the water coming out of the intake but I have to think that with an 1800 gph pump it is strong. So with the intake coming into the top of the lid, say on both sides of the netpot, going down to about 2 inches above the level of the drains. That would provide lots of aeration and water movement
 
D

Drdre

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Yes lot of aeration but I know I have plenty of it in thompsons system roots are perfect and I know I'm not causing any damage to my roots plus i already got the problem of my roots growing to the point they are so long they are growing down the drain now if the drains are even some what close to the bottom roots are going to grow down them and end up in your res which causes clogged pumps if you don't got a filter which I don't
 
joehank

joehank

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Right. I was thinking that feeding from top would push roots down and away from the drains. The drains need to remain at the height that you want your water at
 
J

Jalisco Kid

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Your roots should be so extensive that the top feed water will run out the drains before being thoughly mixed. DD always under pumped his designs. An 1800 is just asking for trouble, in my very unhumbled opinion.
 
joehank

joehank

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Isn't the 1800 size what most people are using for MPB's or UC's ? What would be " ideal" for a 6 site setup?
 
J

Jalisco Kid

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There is no pump per tank answer in my opinion. It depends on your design. Head,90's, filters,back pressure bleds, valves, etc etc. I used to think it was just about max flow but now I have stumbled across a few tricks I realize size counts if you can put it in the right place. If you look at growers running these types of sys for Years successfully you might notice they have larger pumps. Since this is not my design I will let it go at that. But I have always told DD and his guys they were undersized. If you had my Tanks I would use a 3600 min for 6 tanks. I mainly use 4500 gph as my min for 12 tanks and they are feed by large pipes min back pressure,for max satisfaction. You have to not worry about the overhead when running high performance equipment. And the pump is the heart of the operation.
 
joehank

joehank

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I agree. So you would suggest bigger pump for a 6 site MPB setup with the 27g totes that folks are using?
 
J

Jalisco Kid

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As a shot in the dark I would say yes. But as I said It depends on the system/construction. Before you ask that question I would ask myself what am I trying to gain doing so and would that do it for ME. There is a reason I use large pumps in all my designs but I have no clue without seeing your work if that would work. I am looking into showing some of my work here at the farm. If I can you would be able to see where i am going with in my room designs and how they would compare to your or other systems. We will just have to wait and see what happens with that. JK
 
Capulator

Capulator

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I run 3600 gph on 9 sites and it doesn't seem like enough. My next rebuild I'm going with a water fall pump and 1" line, instead of 3/4". Probably will split it in to a couple of feeds per site as well.
 
J

Jalisco Kid

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I would go bigger then that if you can afford it. I would go with a pump with 1.5" fitting. Better to have a high vol not high pressure. (most of the time) JK
 
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