DIY Discreet Mini-Fridge hydroponics system

[Roy]

I was looking for a small, discreet way to grow hydroponically and I figured that with all the different cabinets out there the best is probably a larger sized mini-fridge, becuase it's already designed to handle air, water & light well. In looking for a step-by-step guide online, I didn't find one, but I did find some very flashy websites selling such systems starting at $1100. That price seemed very high to me.

I've decided to build my own system and post all the materials, steps with photos online. I figure I could do this for well under $500, all told. Since I am an absolute beginner (I've killed every plant I've ever touched), I will probably need lots of help.

I plan to test it by growing Basil, Cilantro and Mint in my kitchen. It'll be good for me since I like to cook and winter is on it's way. I know they dont' grow the same as cannabis, but close enough, I figure.

The first step I've taken is looking online and in thrift stores for a larger sized dorm-room style mini fridge - preferably that isn't working as a fridge but looks good and is clean. I found one immediately, almost for free.
The mini fridge is about 36"x22"x"18; ~9 cu.ft.

My next will be visiting the local grow shop for a flourescent grow lamp and other supplies, here is my shopping list so far with expected costs;

150w fluorescent grow lamp - 65
lamp fixture - 60 (!?.. must be cheaper way)
mylar - 15
wiring - 10
air pump - 15
airstone(s), tubing - 10
tupperware and plant cages - 15
fans - 40
carbon scrubber (DIY can method) - 30
plant food - 40
electrical timer - 20

There are certain things I plan on scavenging for in thrift stores and others I plan on buying new - things like the fans I want new because they have bearings that wear out over time. I also want new clean tupperware and tubing because I don't want to risk traces of algae or mold being present.

I hear a lot of talk about how hydroponics are difficult for beginners and you should grow in soil, etc., but honestly I have done plenty of reading and hydroponics doesn't sound very complex at all.

I have heard rumors about how using a fogger can increase your yield and make plants grow faster but I'm skeptical, especially about maintenance issues.

So what do you think? Will one 150w fluorescent lamp be enough? How many plants (I'm assuming Indica/Sativa mix or just Indica) could one expect to grow in about 9 cubic feet?

As for the water I've read that you should use a mix of plant food and suppliments with B1 vitamins, etc.

What's best - rockwool, hydroton, clay pellets? I've seen so many different things.

 

[zipflip]

definately would wanna look into LST supercropping etc.. keep em down in size but maintain ya yeild

ur 9 cubic feet u got minus the cubic feet ur hydro resevoir will take up and wat ur lighting will take up
5000 lumens per square foot grow space(lighting)optimal. ur cfl should say wat the lumen output is on package.
sounds like pretty cool idea. maybe try some auto flowering strains. i been readin on em and hear they perfect for micro size grows FYI

 

[papabeach1]

check massprod s bubbler...

works on my babies (not clones) will post pics in my thread..

 

[The Hemp Goddess]

I have always thought that a frig would be a great place for a stealth grow--light tight, insulated and older ones always have fan/compressor noises coming from them.

I would seriously consider a 150W HPS for flowering ($20) rather than a fluoro--the difference is amazing and the 150W HPS isn't that hard to cool. I agree with Zip, I think that SCROG, supercropping or LST will help your yield.

 

[Roy]

It looks like HPS are much better for lights so I'll go with that. At first I was stunned by the prices until I discovered you could get ballast kits for 1/3 the price of buying ballasts. A little saudering and finding an enclosure saves $100.

Building the hood and reflectors should be no trouble. As far as ventilation goes I've built plenty of computers so I'm not worried about keeping it cool.

I'll be picking up a "non-working but nice looking" small fridge this weekend so I'll order the ballast kit in the meantime. I saw one for $45 that comes with a bulb, but then there are three versions going up to $75. I don't know what difference the size of the base makes.

"atlas lighting supply" (google that, I can't post URLs yet.) has the kits that come with a bulb.

bubble rocks look like a good idea, perhaps a fogger if I can work out the tub right, and perhaps some type of ebb and flow system? I don't see whats so much better about flooding/draining when you can just change out the water/food regularly. I'm still foggy on the fogger idea.

thanks all for the advice this is priceless.

 

[zipflip]

yeah but wouldnt an HPS in a mini dorm size fridge get too hot irregardless of circulation bein so small a fridge minus the space for ya res etc etc. the light wit ballast would practically be layin on plants. i think ya need a bigger fridge man. get one them taller mini fridges. they come in fe sizes i know...

 

[The Hemp Goddess]

It looks like HPS are much better for lights so I'll go with that. At first I was stunned by the prices until I discovered you could get ballast kits for 1/3 the price of buying ballasts. A little saudering and finding an enclosure saves $100.

Building the hood and reflectors should be no trouble. As far as ventilation goes I've built plenty of computers so I'm not worried about keeping it cool.

I'll be picking up a "non-working but nice looking" small fridge this weekend so I'll order the ballast kit in the meantime. I saw one for $45 that comes with a bulb, but then there are three versions going up to $75. I don't know what difference the size of the base makes.

"atlas lighting supply" (google that, I can't post URLs yet.) has the kits that come with a bulb.




bubble rocks look like a good idea, perhaps a fogger if I can work out the tub right, and perhaps some type of ebb and flow system? I don't see whats so much better about flooding/draining when you can just change out the water/food regularly. I'm still foggy on the fogger idea.

thanks all for the advice this is priceless.

Check out this link for an inexpensive HPS:

http://www.e-conolight.com/Product/EProductDetail.asp?ProductFamilyID=7&FGNumber=E-MT6H151G

I don't know what bubble rocks are, but IMO, I would forgo the fogger--you just don't have enough room to put in anything non-essential.

 

[Roy]

Thanks for the link the floodlight option looks good, it definitely measures up much better than the fluorescent options. It may be a challenge to keep it around 78 degrees in there but I have some ideas for airflow.

I'm picking up the mini-fridge on Thursday, I plan on posting photos every step of the way. Space may not be such an issue once it is gutted out. It's 34" tall. The bottom rear corner is raised for the refer unit, but refer unit will be discarded so I may cut that out and alter the floor to gain space. It'll be easier to see how it will all work once I have it in my hands.

 

[zipflip]

Thanks for the link the floodlight option looks good, it definitely measures up much better than the fluorescent options. It may be a challenge to keep it around 78 degrees in there but I have some ideas for airflow.

I'm picking up the mini-fridge on Thursday, I plan on posting photos every step of the way. Space may not be such an issue once it is gutted out. It's 34" tall. The bottom rear corner is raised for the refer unit, but refer unit will be discarded so I may cut that out and alter the floor to gain space. It'll be easier to see how it will all work once I have it in my hands.

i'm a watch along man. sounds like fun project ya got goin on. this is more the route i wanted to take too. i mean do it from scratch. like totally fabricate some stealth type grow box. i see fridges like this at garage sales all the time under 30$ they got one onsale a mini fridge thats pretty large yet. might be lil more than 34 if ya able to go bigger(space?) but it on sale for only 54$ here at our walmart and it black pretty sleek lookin. stealth black....lol
or even go to any appliance repair or sale store. they have TV's and microwaves fridges mini and large deep freezers etc... they throw out all the time. the sales stores when they deliver stuff to people who buy and wanna get rid the old one they're replacin they usually have the delivery people take it and most the time stuff dont run anymore or too old or somethin to where cant resell it. so they toss em. just call em ask them to hold one for ya. i do this alot wit old deep freezers and uprights this time year. i get em bout 10 dollars and i'm good with repairs and i fix em up and put adds in the papers and wat deer hunter doesnt need extra freezer space this time year and how many of them and you all look to buy a cheep used one just for this. well here i am wit some LOL

 

[Roy]

I picked up the fridge the other day and was pleasantly surprised to find it was the largest "mini" fridge I've ever seen. It barely fit in the car. Instead of 18" wide like most mini-fridges this thing is about 24"; measures about 23"x23"x34". Of course the interior dimensions are smaller (but will be larger once I gut it out). It's listed everywhere as having a "4.9 cu. ft. capacity". If you're curious it's a Sanyo model SR-4912M.

I did go ahead and buy a 150w HPS floodlight from the e-conolight website (thank you Goddess).

My main concern is of course cooling it down, I plan on using two large intake fans on the bottom-rear and two large exhaust fans on the top-front. I also might mount the floodlight outside the case shining in with it's own cooling ducts. Once all that's set up I'll try and test it, but I'll be very surprised if the fans alone keep it cool enough. I expect that some type of active AC system will be needed.

For cheap and effective enough air cooling the best answer I've found is a device using a peltier plate. If you search instructibles website for air cooler/heater peltier you'll find one kid genius's project. Also if you just search eBay for 12V cooler you'll get basically the same thing with a nice case and matching price tag.

The typical hydroponic setup looks (deceptively?) simple from afar, not having enough equipment to test it yet. I need to just go to the nursery and get enough supplies to start growing greens on the balcony just to test my plan. That plan is a black rubbermaid tub with holes filled with baskets of vermiculite, little nylon ropes within leading to the tub filled with water + nutrient solution, and an air pump pumping air through a fishtank bubble-stone thing via tubing. I figure the nylon ropes should both wick the solution into the vermiculite and aid in aeration.
So I guess I'll just set it up like that, then just replace the water/solution every X days, etc., maintain the pH balance ..?

.. actually maybe a better plan; cut out the floor, raise the thing up a bit and put in a new floor, seal that up, have only tubs of vermiculite inside, mount a flat reservoir for the nutrient solution outside on the back of the fridge with a water pump making it an ebb/flow system. that would create & free up way more space inside..

 

[andy52]

if you are going hydro,you also need a tds meter.

 

[Disco94]

With that fridge you could do an Auto-Flowering Dwarf strain like Lowryder and its crosses if you haven't thought about it. Throw some CFLs in there and you would be set if the fridge is setup

 

[garethjones]

Nice idea dude....

upload some photos of your invention...