nope, no special plastic needed. nothing will leech out in dangerous ammounts. you can try rinsing them out with warm soapy water and leaving them out in direct sunlight for a few days to get rid of that smell but it wont hurt you or the plants.

One question about the rubbermaid container. Can you put a water heater in it like you would do in an aquarium. It will heat the water to about 78 degrees. Is the plastic safe enough and not melt.
Any input appreciated.

I have used an aquarium heater with few problems. Just make sure you use the proper wiring - always use a GFC circuit when using electrical devices in water (BE SAFE). As for safety of the plastic, the previous poster is correct. To get rid of the plastic smell, clean with a soap and diluted bleach mixture in the container, and then let sit in the hot sun for a while. The plastic will out-gas and then no longer smell. I have used the same Rubber Maid container in a bubbler system for six years.

Good Luck
Dennis
www.crescenthydroponics.com

Hi, basically any plastic labeled as number 2, 4, or 5 is ok for food. Although I don't agree with everything on this web site link I"ll paste in here, they do have a good summary (PDF file) of different types of plastics and what leaches out of them:

http://www.lifewithoutplastic.com/factsonplastic.htm

The PDF file is near the bottom of the page, but actually the page itself pretty much summarizes it all.

I am also going to be building my first rubbermaid system in a few days, which will also be my first hydroponic system. I would eventually like to experiment with other materials though, even though they will be more expensive I imagine - just to be able to get away from using plastic.

I'm not a fan of PVC pipe, even though my house has it. It's safety seems questionable as well.

What is "rubbermaid" made of? (which plastic?)

Rubbermaid is plastic. There is a FDA approved food safe rubbermaid reservoir just click the link below.
I do not know if the ones in WalMart and Lowes and other places are safe -AND- the ones I have seen are pretty thin. I would be afraid of solution leaking out.

Here is a link that might be useful: Food Safe Rubbermaid Container

dancinglemons:

Yes, thanks for the link. It is exactly that type of "roughneck" container which I plan on buying. They are significantly more rigid / thick than other storage containers and as the link says they block a lot of light but not all. It is however encouraging to see that if you get the "indigo blue" color it blocks algae growth, according to that website. It's encouraging to see a hydronic dealer selling them for this specific purpose :)

Also I've seen these containers used even in the how-to hydroponics book written by Keith Roberto, and some of them are outdoor systems.

My only major current concern is the temperature of the nut. soluction. I plan on getting some type of submersible thermometer to lay on the bottom of the reservoir so I can track how that's doing. It'll probably be ok now heading into winter but I may have to sink the container a foot or so into the ground come summertime - not sure yet.

habman,

Thanks for asking the question. I was wondering the same thing myself.

dancinglemons, thanks for the link. My local wardware store carries that very same rubbermaid.

Bill

The Roughneck bins I've bought in the past 10 years develop a slimy film and any stored clean linens get very smelly. Even though I use them for non-linens as well, I will have to replace all my bins in order to avoid incompatibility in stacking. Older Roughneck bins that I own do not have this problem, but will still be replaced. :(

HDPE, and PP are best and easiest to find in food-grade. Any plastic definitely cannot be used in hydroponics as some plastic polymers do not have the chemical resistance to withstand the nutrient chemicals over time. A brand that uses food grade plastic is Dovegrow.