Do not try it!! Please rember that all the nutrients are in the form of salts to be usable for plants and that galvanized anything is covered with a metal that rusts and then falls off quickly to keep the base metal from rusting This is a recipe for disaster. If you want a idea how fast this can happen try putting some of your uncut sulition in a coffy can and watch what happens in short order.stick to the pvc. Have FUN

i'm experimenting with it for orchids, using a pond fogger and delivering a weak nutrient solution out of a resevoir.

i have heard of people having botrytis problems, but i've been alright so far. also, it's not exactly clear to me (maybe someone else will know) but how many minerals in the solution are actually present in the vapour. obviously from the dust there is some, but when i used my digital tds meter, i've found that as the water is vaporized and the level in the reservoir drops, the tds increases at almost the same rate. put another way, after half the water is vaporized, the remaining half has roughly twice the minerals of the initial solution.

who makes your fogger btw?

so are you saying for my tds that i need to either change out my solution or add more water to compensate. cause i am growing without testing. :-0 so am relying on others for input probally should test :-( but cant afford it right now but will). i test ph and ec but are the tds really that important when fogging. by the way i will be using pvc or something like that thank you. the fogger i have is also a pond fogger, and i dont know the maker it just says mist maker unit. it atomizes 1100 ml/p/h and has 9 heads. to tell the trugh i found a 10 head that did 3000 ml/p/h so am a little up set about my buy but will get over it. by the way do you have any ider how much 6 inch pvc a fogger of that capacity can cover evenly? cause i sure dont know but would like to.

what is (botrytis problems)? so do you have a link to somethin that can inform me about it. i have never heard of it i am new to all of this. and are you using a pump to circulate your solution as the fogger is working so that the minerals are not falling to the bottom. and if so are you using a distilled water free of minerals that also might help. i really don't know. just a possible?

botrytis is a common fungus that attacks plants. if you google it, youll find much better information than i can probably give you.

i don't have a greenhouse (one day..) so for now i grow in tented enclosures. it would be more or less the same thing, on a lesser scale. my fogger is a three disc, which is overkill for the area i have to cover, but because i want to make sure theres maximum possible co2, and to prevent molds and fungus, i want to keep a high airflow (even though its a bit at odds with the fluid dynamics of the fog). for me, even blowing an air stream through my growing area, i can keep saturation dense fog. that cylces on/off every four hours, which is what the orchids seem to like as they have an oppurtunity to dry out a bit in between.

i have a friend growing salvia under constant vaporisation, and he hasnt had any problems. our solution is flowthrough ventilation, something that might not be feasible in a greenhouse setting.

i dont have any experience with the larger commercial foggers, but ive gone through tens of retail models, and the two discs sizes ive run into seem to correlate to the volume of vapour they produce. if your system uses the same technology then i could probably guesstimate that a nine disc could adequately cover a large sized bench of seedlings with a reasonable amount of air circulation. though then again, a nine disc could probably fill a sealed backyard greenhouse fairly quickly.

this is all dependent on your fogger being similar to mine, obviously. ive seen some commercial greenhouse foggers that sabbath would envy.

as i understand it, your tds is a combination of fertilizer and the minerals initially present in your water. i only use RO water, though distilled would certainly be acceptable once you add a bit of minerals to it for stabilization. what i said about the solids staying in solution is just colloquial, so dont necessarily take it on one guys say-so. ill see if i can collect and condense some vapour, meter it, and maybe resolve the question.

hope something in here is helpful to you. good growing. :)

well to tell the truth dustin i am wanting to use 6" pvc and a fan to force my fog in to the pipe. but i need a very low cfm fan, to move the fog. do you know of any 110 volt fans with around 20 or less cfm, or maybe adjustable air flow. btw how big is your reseviour, and how often do you have to fill it up? the reason i ask is i have to haul all my water cause the water from our well is to say the least nasty as hell!! but in other words it is very heavy on the sediment side ok for showers an laundry, but probally not for fogging. to go back to a previous post i believe it already has a high tds, but dont know.

anywho happy growing to you

that sounds like a great idea. are you thinking of impelling the air flow or propelling it? i ask since the water droplets seem to condense and dissappear if theyre treated too roughly. like a sort of inside-out cavitation.

everyone in the terrarium forum seems to use "muffin fans", computer cpu fans rigged up to ac/dc adaptors (i have no idea where "muffin" comes into it..) but the cfm is considerably lower than something like, say, the ac inline heating duct boosters you can get from home depot.

my reservoir is a two hundred or so gallon black pvc rigid pond liner, filled about halfway. i plan on piping RO directly into it with a float valve, but for right now its a bucket a day.

you may want to have your water tested, even if you are thinking of buying a reverse osmosis system, as excessively high hardness will severely shorten the life of your membrane. i believe in that case you might need to use an ion exchange water softener first and then connect that to the ro system. a simple aquarium test kit should be able to provide the answers.

anyways, it sounds like youre going to have a pretty neat system when its all done. be sure to post pics.

How do you post pics on here. so about 5 gallons a day or so?

yeah, about that.

i believe you can use raw html tags.

[img src="http://path.to/your/image.jpg";]

and substitute "" for "[" and "]"

lets try..

{{gwi:998540}}

yup thats it. :)

This is a very interesting thread. I have just a few comments.

Akfog if you adapt a small personal desk fan say 7" or less with an ac speed controller you should be able to kludge together an air flow source that will allow you can vary the amount of air flowing through your fogging chamber. Here's an ac speed control link I found interesting. http://www.kbelectronics.com/data_sheets/kbwc_data_sheet.pdf

The only caveat is that motors tend to run hotter with solid state speed controllers. The link above recommends the fan being controlled have built in thermal protection.

Dustin_b observed that the EC of the nutrient solution increases over a short time period as opposed to lowering as the nutrient is being consumed. I was scratching my head for a while trying to figure out how this was possible. Here's my theory, and it's just a guess. As the fog saturated air condenses on the roots, medium, walls of the container, etc. and because there is air flow water and only water evaporates away leaving behind the nutrients which over time increases the concentration, thus you have your EC increase. I can't see how the fog (being droplets of 5 microns, huge relative to ion molecules) would be less concentrated than the solution itself.

I can see why maintaining a constant water level is important using this technique. The need to measure EC levels is also quite important. Minimizing air flow is a good thing. This will lower the evaporation rate and keep your fog droplets which escaped the system from being wasted. But, roots do need oxygen so air flow is important and you need air flow to get the fog to the roots. The question then is what is the optimum rate of air flow?

thank you dustin and hank for you help. i will be posting when i get everything up and running. so if i just ad water will that help with my ec and tds thats kind of what it sounds like? i guess if your fog is coming back to your tank i can see how the tds would increase. but i am thinking about just porting the left over fog outside maybe that would cure the tds doubling with water droppage. really dont know just a thought

oh by the wayi made my first ordhid purchases. they are thepaphiopedilum "lady slipper", and the phallaenopsis "moth orchid". the second doesn't flower for 4 years so we will have to wait for pics on that one. the first i believe takes 1-2 years for flowering to occure. i was wondering if there was any way to accelerate their growing time to get flowers sooner. i am going to do some research on that. but if anybody has any suggestions i would be happy to hear from you.

Here is a nice economical site for a nice squirrel cage fan either ac or dc and CMF from 6cmf on up.
http://www.surpluscenter.com/sort.asp?UID=2005031513035756&catname=electric&keyword=EBSA

how high is the relative humidity where you are planning on growing your orchids? and what are they potted in as you can tell?

thanks for the low cfm fan site.

and i dont really know the humidity, but i am considering growing my orchids inside. maybe in an aquarium with a smaller fogger but plan on using my larger one for the actual greenhouse. i guess i am also looking for a cheap way to do all of my water testing. in other words the PH, the EC, and the TDS. if anybody knows i would be greatful.

i use the trimeter listed at the attached page. its not exactly cheap, but its good for live monitoring on a hydroponics reservoir.

humidity meters are only about ten dollars though, you are well advised to pick one up. the results are often surprising.

Here is a link that might be useful: nutradip