Stainless Steel RDWC for outdoor/greenhouse

Wanted to show you guys my latest project. I'm building a stainless steel RDWC system. Because outdoor/greenhouse RDWC and I wanted it to last forever. Being a mechanical engineer has its perks.

Everything you see here is 304SS. I ordered it too thick at 16ga, so the next ones will be 20ga, but regardless, I'm excited for it.

These are 8 gallon containers that will spend more time in veg than anywhere else, long term. I'll probably end up flowering in them once or twice. I'll move to much bigger containers later on.

Overall, I'll be spending about $250 per container when all said and done. That includes all the piping, reservoirs, pumps, etc. This is also for 20+ containers. It would have been like $500 ea if I only had 5 or 6 made.

Basically, I'm spending twice as much as a Current Culture system and probably three times as much as some hacked together system made from fuck all. But I will never have to worry about things breaking, getting damaged in moves, etc. This will last me for 30 years.

Nice...waste of money IMO..but nice.

redi jedi said:

Nice...waste of money IMO..but nice.

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Never having to replace these again for the next 30 years? Definitely not a waste of money.

MisterBlah said:

Never having to replace these again for the next 30 years? Definitely not a waste of money.

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A plastic container can last 30 years also...

You can buy alot of buckets/containers for $200

redi jedi said:

A plastic container can last 30 years also...

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A thin plastic container can also be broken during a move or due to some accident or whatever.

redi jedi said:

You can buy alot of buckets/containers for $200

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You are right. I could probably buy 100 of those 5 gallon buckets.

Plastic is alot easier to work with too, most people will have a real hard time drilling a hole in SS. Work hardening is a bitch.

Just on your raw material cost you've spent ten times what I did for my whole system.

Not knocking your approach one bit. My stuff does slowly chip and degrade, but I've kit bashed everything. As I'm able to begin doing my own designs I also expect unit coats to rise, along with durability.

redi jedi said:

Plastic is alot easier to work with too, most people will have a real hard time drilling a hole in SS. Work hardening is a bitch.

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I didn't drill holes in anything. The shop that made them does all that. I think the pictures just don't show any of the holes.

as a ss fabricator/welder for 15 years i have to agree that its probably a waste. i thought of doing the same thing when i was building my rdwc system but ultimately went with plastic. A properly built system will last a long time and my 35gallon containers where $8 each solid black and are nice and strong. I like the idea but like I said its way overkill for hydroponics. btw who welded it? if it wasnt back purged the oxidation will contaminate the inside, and also 304l isnt what you wanna use in a situation like this. its a pretty low grade and will most likely corrode after a while. I HAVE seen it happen many times. 316l is the way to go, which is why its used in the food industry. I still may attempt something like this some day but not a big system. maybe a single. I seen a guy selling a single plant reservoir at a convention a while back that was stainless and he wanted something like $1500 each for it. I think it cost me less than a hundred bucks to build mine (minus pumps) and has been going strong for years. Again, not trying to bash you because its a good idea but its only good for personal use. I doubt there would be a market for something like this unless maybe commercially. good luck with it.

This is excitng stuff..

I've read these forums a while now, most of it becomes boring. This is the first time in a while something different has been done.

If you can afford it, if it can be utilized then its no waste. I look forward to detailed pics.

gand3r said:

This is excitng stuff..

I've read these forums a while now, most of it becomes boring. This is the first time in a while something different has been done.

If you can afford it, if it can be utilized then its no waste. I look forward to detailed pics.

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There's a thread over at THCfarmer. Dude built a SS rdwc. I forget the name of thread, but its in the tree farming forum.

8 gallon seems on the small end.

I think I was quoted 350 dollars a tank for the large UC pro ones.

- Jiji

I believe these will be used for veg, 8 gallons should be fine.

The issue will be transferring into flower, I would have the new containers made so that the lid fits as removing the vegd plant with a large football may be a bitch.

redi jedi said:

There's a thread over at THCfarmer. Dude built a SS rdwc. I forget the name of thread, but its in the tree farming forum.

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I've seen it. He said it would cost over $500 per site for a finished system. I'm down around $200-250/site for a finish system at this size. I don't remember what size his tanks were. But the waterfall he creates in every container is what makes it so expensive.

jijiandfarmgang said:

8 gallon seems on the small end.

I think I was quoted 350 dollars a tank for the large UC pro ones.

- Jiji

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I have some larger containers out for quote right now, but I anticipate them being not that much more expensive, TBH. And I've also got some designed that will serve as a single site for multiple flowering plants. So, 40+ gallons and somewhere around 42"L+ x 24"W x 12"D. The cost for me to get a new size made is about 30 minutes in Solidworks. Bent sheet metal is pretty inexpensive and doesn't require tooling.

gand3r said:

I believe these will be used for veg, 8 gallons should be fine.

The issue will be transferring into flower, I would have the new containers made so that the lid fits as removing the vegd plant with a large football may be a bitch.

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There's some really wide rimmed net pots that I would recommend for veg for these.

An P Eng huh, I would have never guessed lol. I put my youngest through university as a P.E.C and she is now making me spend twice as much for everything I build lol. Not a bad thing though, don't get me wrong! It will be nice to see that thing up and running, I expect the control system with be as worthy .

Budley Doright said:

An P Eng huh, I would have never guessed lol. I put my youngest through university as a P.E.C and she is now making me spend twice as much for everything I build lol. Not a bad thing though, don't get me wrong! It will be nice to see that thing up and running, I expect the control system with be as worthy .

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Believe it or not, it won't have a very sophisticated control system. Maybe pH control at most. Water quality analysis can't be done in real time very well, at least, when testing for most macro/micro nutrients. So, I send them off to a lab to get done and I adjust my fertilizers based on the results I get back.

MisterBlah said:

Believe it or not, it won't have a very sophisticated control system. Maybe pH control at most. Water quality analysis can't be done in real time very well, at least, when testing for most macro/micro nutrients. So, I send them off to a lab to get done and I adjust my fertilizers based on the results I get back.

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Ya I pour mine in till the tips burn a tiny bit then I cut back lol. A 50 ml Tupperware bowl for the down. I get my nutes from a lab that makes and bottles for others and them selves called ez-gro and have great results, also a bit of Aqua-flakes.

jijiandfarmgang said:

8 gallon seems on the small end.

I think I was quoted 350 dollars a tank for the large UC pro ones.

- Jiji

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I just got back quotes for the last of the stainless parts I need to make 35+ gallon containers. If I were to offer these for sale, I can be price competitive with current culture on their big 35gal UC Pro buckets and do it using stainless steel.