hmmm.i have double wall polycarb.have never had a problem w/moss-or is it some sort of algae?i did seal the top edge with aluminum tape.but i left the bottom open.after a big rain,and a few cloudy days,mine does definitly develope some condensation inside the double wall.but a full sun day dries it out.well,i guess it just heats up,and then drips out the bottom.does your greenhouse get full unobstructed sun.any trees,buildings ect blocking the sun?is it angeled properly for maximum solar gain?

Hi trigger m, I don't get as much sun as I would like as I live in a clearing in the woods. I guess my question is can I pour/put something in the gutters to slow down or kill the moss. I have a frog or two living in the GH so I really don't want to use anything too toxic. I was thinking baking soda, diluted bleach, or vineger and was wondering if anyone has had any experience with useing these products on moss. Here is a link to show the problem.

http://img.photobucket.com/albums/v730/bamboomary/Mossintriplewall.jpg

Damnedest thing. The bottom part of the poly sheets are suppossed to be open to allow drainage. I would contact the mfg of the poly and inform them about the moss and also ask how they suggest to resolve the problem. It can only get worse! The mfg's certainly wouldn't want info like this to get out.

I have contacted the manufacture (Charleys) and they suggested the diluted bleach. They didn't/wouldn't say whether or not this is a big issue and I just didn't feel real confident with this suggestion. That is why I posted this question. I had searched all gardenweb forums without finding an answer. Maybe I'll just have to try the bleach suggestion and hope for the best......

I would ask Charlie's about using Oxyclean- I expect chlorox would be more damaging to the plastic. If there is enough water for the frogs you will never eliminate the growth- but you can make it look better. To protect the wildlife flush all of it with a hose first, and after you have let it sit(20 min may be enough - I would go overnight)flush it well again
John
I checked your photo the moss ought to be removable just by weeding?

The install instructions that came with my poly deffinitely called for sealing both ends. The bottom seal was a piece of U profile plastic strips. They are about 3/4 of an inch wide and 8 ft long, you cut them to fit and they are screwed into place. Weep holes are drilled along the bottom every 12 inches to allow condensation to escape.

I bought mine from Sundance Supply. Perhaps you can get some of these and try to install it with the panels in place.

jb

I was told to use a filter tape along the bottom of the panel. It lets moisture out and also keeps out any debris or insects. I would test any bleach or chemical cleaning on a scrap piece first.
DJ

polycarbonate is very inert, I doubt anything you use to clean it will be harmful (polycarbonate is a common replacement for glass in chemistry 'glassware'). Having said that, I would test on a spare piece too :)

This is a list I received from Gothic Arch Greenhouse on a data sheet from the PC supplier. I simply re-typed them here. I am not recommending use of any of these chemicals on your Poly. I am simply passing on info...(My CYA statement)

Chemicals that will DAMAGE Poly Carbonate:

Acetone
Acrylonitrile
Ammonia
Amyl Acetate
Benzene
Bromine
Butyl Acetate
Caustic Soda
Chloroform
Dimethyl Formamide
Hydrochloric Acid-Conc.
Hydrofluoric Acid-Conc.
Iodine
Methanol
Methyl Ethyl Ketone
Perchloroethylene
Styrene
Toluol
Sulphuric Acid -Conc.
Xylene

The Following require CAUTION:

Cyclohexone
Diesel oil
Formic Acid
Gasoline
Glycerine
Heating Fuel
Jet Fuel
Perchloric Acid- Conc.
Sulphur Dioxide
Turpentine

The Following are considered SAFE:

Acetic Acid
Ammonium Chloride
Antimony Chloride
Borax in H2O
Butane
Calcium Chloride
Calcium Hypochloride
Carbon Dioxide
Carbon Monoxide
Citric Acid 10%
Copper Sulphate
Ethyl Alcohol 95%
Ethylene Glycol
Formaline 10%
Hydrochloric Acid 20%
Hydrofluoric Acid 5%
Mercury
Methane
Oxygen
Ozone
Sulphur
Urea
Water

It would be nice if we could stick this in the FAQs. I know someone is going to ask about this right after this post drops off...

It would be nice if we could stick this in the FAQs. I know someone is going to ask about this right after this post drops off...

Done.

WOW Very Cool. You're so smart, I never thought to do that. Great Idea...

Many thanks to all who responded to my question. Weebus, thank you for the great link, it was very interesting and I feel better about using the bleach solution now!
Happy winter gardening and happy New Year to all.