DIY compact ebb-flow system

[naoki]

I just made a small ebb-flow hydroponic system for my Disa uniflora. I thought that some people may be interested in. Most parts are from Lowes/Home Depot.

Parts:

• Sterilite 27 gallon plastic container (for the grow box), $15.55 from Walmart.
• Rubbermaid Roughneck 18 gallon plastic container (for the reservoir), around $12.
• PonicPump 12005 (submersible pump used for fountains, 120GPH @ 0' lift, 6W), about $14
• Watts PL-1871 1/2" Bulk Head Union, $10.98 from Lowe's
• Watts LFS-385 Brass Hose barb (1/2" ID x 1/2" MIP), $4.58 from Lowe's
• kbi TMS-0500 1/2" MIP to 1/2" CPVC adapter, $5.10 from Lowe's
• 1/2" CPVC street elbow, $0.98 from Lowe's
• 1/2" CPVC (short section)
• 1/2" vinyl tubing (5/8" OD x 1/2" ID), 7' for $3.15 from Lowe's

Total: about $67

I got two plastic containers: one is for the growing space and the other is for the water reservoir.

First, I made the drain hole to the growing case. Since the plastic is a bit flimsy, I decided to use a bulk head union. Without thinking too much I started to drill with a hole saw.


Oops, it is not a good idea, and this is what happens. I should have used a supporting block and/or duct tape.


Well, I had to go back to Walmart to get a new box. This time, I used a soldering iron (toxic but less likely to screw up). I put a nail to the soldering iron because I didn't want to ruin the soldering iron tip.


The bulkhead is attached:


Here are the other parts needed.
From left:
Brass Hose barb (1/2" ID x 1/2" MIP), which is screwed into the bulkhead from outside, and it is connected to the return tube to the reservoir.
1/2" MIP to 1/2" CPVC adapter
1/2" CPVC street elbow
1/2" tubing


Attached the hose barb adapter to the outside. I had to use the Teflon tape for plumbing for this connection (otherwise, it was leaking).


Here I'm showing a street elbow (one side is male, and the other side is female) attached to the MIP to CPVC adapter. I'm drilling two small holes (5/64"). These small holes make the water to drain out slowly.




Now, I cut a small section of 1/2" CPVC. The length of this pipe determines the water level when the water is pumped in to the growth case.


Now I attach the assembled elbow to inside of the bulkhead. Here is the inside view of the bulkhead.


Screw in the MIP to CPVC adapter. Then attach the elbow and the drain pipe. The CPVC parts are not glued, just friction fitted.


I made two tables from a cedar siding plunk that I happen to find in the backyard and legs are from some branches that I found in the firewood pile. Later, I painted these with water-proofing Elastomeric paint (frequently used for roofing). Also I made a hole to the top right for the water supply tube. The water pump supplies water through the tubing through this hole.


Assembly done:




I made a green table from left-over lumbers and set up the system inside. I made two holes to the cover of the reservoir: one for the tube going to the growing box and one for the returning tube.

 

[naoki]

Here the water is filled up. The water will gradually return to the reservoir through the two small holes of the elbow. I adjusted the height so that it reaches to 2/3 of the pot. I can adjust the water level slightly by tilting the elbow.


Finished view. I'm hanging a DIY LED. This is 20W COB LED from ebay, with heatsink from a washing machine. It is crappy LED (and not strong enough for Disa), and I'll probably change it with a more efficient one. 2015 version of Vero 18 and 29 should be available really soon.


Some of Disa was growing in Perlite+sphagnum moss. I top-dressed with aquarium gravel, so they don't float up when water is filled up. Some of them weren't doing well, and I hope this Ebb-flow will help them.


The water pump is connected to a digital timer which has 1 minute resolution. Then it gets turned on twice a day for 10 min. The plants will be soaked in the water about 15-20 min each time.

It took a bit of time to make the table, but the ebb-flow system part would take about 30 min to assemble. I used a tall container for the growing box because our ambient RH is low, and I wanted to keep RH high. For now, I'm keeping it open top since it can keep around 60-90% RH. In the winter, I'll probably need to put the cover.

 

[Marco]

Awesome setup. I'm sure the Disas will love the water flowing by their feet.

 

[NYEric]

Why ebb and flow instead of constant circulating water? Are you using RO water? Do you filter/purify the water before returning it? Where did you get the Disas?

 

[cnycharles]

nice show of setup. if your pump isn't completely sealed inside like many aquarium pumps, your water can flow back down the input hose from the bottom
much more expensive is the step up drill which can cut many size holes and it usually won't crack those tubs though you came up with a good solution! I have a bulkhead fitting on the side of my small tub so that when it gets to height it runs back out into the reservoir (except for when i'm not watching and then the drain gets blocked by a pot or big pieces of bark and then it goes where I don't want it to)

 

[Migrant13]

Nice job Naoki and thanks for sharing all the details. You need a kovachii to two in there as well!

 

[naoki]

Eric, all Disa are from Wally Orchad (Afrodisa). I think you are one of them who mentioned him in ST a couple years ago.

I forgot the detail about the reason why I went with Ebb-flow. There was a Ph.D thesis about Disa culture. Drip-style hydroponic was slightly better than Ebb-flow. I think one of Wally's article mentions Ebb-flow vs continuous flow system for Disa, too (I forgot the detail). I think one simple reason for the Ebb-flow system is that the ebb-flow system uses less electricity (well, this is minor advantage because the pump doesn't use lots of electricity). Also I like the idea that the air in the pot gets purged twice a day during the ebb-flow process.

In the last photo, you can see the return pipe. I'm using those fuzzy stuff (something like pillow filling) which some vendors use to wrap plants as a "filter". I have other ideas for the filter, but I'm kind of cheap, so I like to recycle things if I can. I'll see if this simple "filter" is sufficient.

I'm using rain water (actually snow-melt water this time of year), but in the winter I probably need to use RO water. I haven't quite dialed in the fertilization scheme since this is my first real hydroponic system. The Disa thesis and Wally's articles have relevant info about fertilization with hydroponics, so I need to reread these papers.

Charles, thanks for the info about the step-up drill. I have it, but mine was too small for the required size. It is good to know that the step-up drill works with this types of plastics (I didn't know it). It is better if I don't have to use the soldering iron. I think if I warmed the plastic with hair drier, it might not have cracked with drill. I made the two small holes (for the slow drain) to make sure at least one is not clogged.

Migrant, I saw the video of P. kovachii with Ebb-flow. I have only 3 deflasked seedlings (about 1" leaf) of Pk left (2 out of 5 died within a year). I'm using the bottom water tray for them at this point. I'm guessing P. kovachii and Disa are not likely to be compatible due to their different pH preference. I'm targeting pH 4.5-5 for Disa with white vinegar. So I need to make another one for P. kovachii! But I have Calopogon tuberosus in the Disa system. I'm a bit worried about this Calopogon because it hasn't sprouted yet. Maybe the tuber is already dead? I'm also wondering if Habenaria radiata can be in the same acidic Ebb-flow system (I'm still reading up about this species).

 

[Ozpaph]

What a great project! Well thought out and documented. Thanks

 

[Secundino]

Great! Thanks!

 

[NYEric]

Thanks for the info. I'm interested in getting some seeds or corms but the info on the Afrodisa site was last updated like 6 years ago.

 

[Clark]

Cool!
Takes some time to show on internet. Thanks.

 

[naoki]

Thanks for the info. I'm interested in getting some seeds or corms but the info on the Afrodisa site was last updated like 6 years ago.

Yes, he doesn't seem to update the site. You just have to email him. Wally is very helpful and nice to deal with. Bigger plants are $15-20, and smaller ones start from around $10. Last fall, he gave me 6 D. uniflora for $70 (including shipping). Red, yellow and orange. They were 2 year old, and some are going to flower this year as you can see in the photo.

If you are interested in hybrids, he has lots of them, too. About 1.5 years ago, he had D. uniflora red, D. tripetaloides, D. Kewensis, D. Golden Age, D. Yellow Bird, D Michael Gallagher x D uniflora (shapely red parents on both sides), D. Kewensis, D. Auratkew, D. Veitchii, D. Unidiorosa.

A couple weeks ago, I lost my D. aurata, which flowered last year (which was also from Wally) for an unknown reason. Hmmmm.

I'm not sure if Wally sells seeds, though. Silverhill does have seeds of some Disa species: http://www.silverhillseeds.co.za/byEntireCat.asp They said that they were swamped with order at this time, and they are experiencing 10 day backlog to process orders at this moment.

 

[cnycharles]

The step up drills can be very expensive, but if you shop harbor freight you can get cheap things. I learned of the need from an aquaponics site selling the drain units and the drill bit to make the hole.
Yes wally doesn't keep up the site but just email him he gets right back to you with whatever answers you need
Wally did have seed available before, not sure about now

 

[NYEric]

Yes, he doesn't seem to update the site. You just have to email him. Wally is very helpful and nice to deal with. Bigger plants are $15-20, and smaller ones start from around $10. Last fall, he gave me 6 D. uniflora for $70 (including shipping). Red, yellow and orange. They were 2 year old, and some are going to flower this year as you can see in the photo.

If you are interested in hybrids, he has lots of them, too. About 1.5 years ago, he had D. uniflora red, D. tripetaloides, D. Kewensis, D. Golden Age, D. Yellow Bird, D Michael Gallagher x D uniflora (shapely red parents on both sides), D. Kewensis, D. Auratkew, D. Veitchii, D. Unidiorosa.

A couple weeks ago, I lost my D. aurata, which flowered last year (which was also from Wally) for an unknown reason. Hmmmm.

I'm not sure if Wally sells seeds, though. Silverhill does have seeds of some Disa species: http://www.silverhillseeds.co.za/byEntireCat.asp They said that they were swamped with order at this time, and they are experiencing 10 day backlog to process orders at this moment.

Say What!? I know what I'm ordering on payday!! OMG! This is the most dangerous website on the web!!

 

[naoki]

The growth of D. uniflora seems to be better with the Ebb-flow (compared with my manual daily watering), but it is not still optimum yet. I lost 1 plant. There were days with too much smoke from wildfire, and I couldn't keep windows open, so the room became pretty warm, and this could be the cause of the decline.

One of them bloomed. It is supposed to be orange type. It is red-end of orange.

Disa uniflora '319' (orange) on Flickr

The column structure is pretty different from others I'm familiar with, and I couldn't figure out where the pollinia is located until I looked it up on internet. The two pale yellow tubes contains skinny (but pretty big) pollinia. The darker yellow part at the bottom of pale yellow part is the part of pollinia. The stigma is the white part near the bottom with 'Y'. It was already making several growths for next year, so I decided to pollinate it even though it was a bit risky. It makes a huge fruit. I hope that it will oversummer well.

Disa uniflora '319' (orange) column on Flickr

 

[fibre]

Congrats! What an interesting photograph of the flower details!

 

[JeanLux]

Great pictures!!!! Jean

 

[Marco]

Beautiful. Thanks!

 

[NYEric]

Nice ..but... Flowers would be far from my mind in this scenario!

I lost 1 plant. There were days with too much smoke from wildfire, and I couldn't keep windows open, so the room became pretty warm, and this could be the cause of the decline.

 

[SlipperFan]

Beautiful photos.