My Greenhouse is 10Wx12Dx10h. I currently have 36 Gallons in Covered/painted black Rubbermaid storage containers, under each of my plant benches, with 8 benches, that is just 288 Gallons of water. I have also been building a Wall of blank painted two liter bottles around the outside edges of my benches (Except on the potting bench where I need the low angle light. I also have one painted black steel 55 gallon drum in one corner I learned a few things right away and one of them by accident. The Water Storage being right under the plants is maintaining a very Constant temperature for my soil. I learned this by placing my temperature probe between the water containers and the plants to keep the probe out of direct sunlight. Anyhow, on to the Computer results. My Computer gathers the outside temperature and the greenhouse temperature every 15 seconds. I keep a running graph of the temps displayed on my computer 24 hours a day, and then store the data. The Data Cleary showed a Few different results. 1. Prior to putting the water in, the Greenhouse daytime Temps were easily breaking 110F to 120F 2. Prior to putting the water in, At Sundown, Greenhouse temperatures would quickly drop down to and match outside temperatures. 3. After putting in the water, Daytime temps in the greenhouse have not even exceeded 100F, even without any venting. But here comes the real magic 4. After putting in the water, at sundown the Greenhouse temps will drop down close to outside temps (Around 65F.... but then the magic comes. As the outside temps continue to decrease, the gap between greenhouse temps and outside temps continue to increase, 5 degrees separation at 60, 10 degrees of separation at 50, and 15-18 degrees of separation at 40 (Our lowest temps so far this year have only been 39f), but I look forward to see the results this winter, It would be nice to see 20 to 25 degrees of temperature difference when we go below freezing. All this with less than 350 Gallons of Water, that most of, was easily stored in the unused space under my benches. I am continuously adding two litre soda bottles, and 1 gallon milk and water containers from my house and my neighborÂs house, I am hoping to get enough water in that I will not have to vent heat during the day... Heck if I get enough water in there perhaps I will not have to move my plants out in the summer, if I use some shade cloth. I was thinking about playing with some of the Clear bottles and only painting the side the faces the greenhouse walls black, and leaving the inward facing side clear,(would that allow the heat to escape better at night?

thanks chris, I took your suggestion from last time...I spluuged for a $9 digital thermometer...right now the temp outside 38 inside 44...I dont have a sensor for outside temp but using a weather stations readings about 3 miles away...may vary a degree or 2....all the mators I had died with the exception of a clipping that I took a few weeks prior to our cold spell...that one is still green but hasnt grown at all...I have been bringing my seedlings in at night and tonight brought in christmas cactus that I propergated as well....everything else in there is hardy enough I just cant wait until spring Steve

You would probably not have to do as much venting from my past experience. The water tanks will be absorbing the extra heat, keeping it cooler during the day. I had a passive greenhouse years ago, before I moved. I wish I had the time and energy to build another. The north side was metal,with thick Styrofoam insulation. The south side was double pane glass from a store front with a 4' insulated knee board. I had benches with 55 gallon drums filled with water under the benches. The barrels behind the knee board didn't receive any direct sun, the ones on the north side did. I had a low/high thermometer and an hour meter on the thermostatically controlled vents. The vents rarely opened and the temps stayed between 50 and 90 degrees pretty constant. When I had days with very low temps and no sun, I could heat it with a Coleman propane lantern! I don't see a location for you, I live in SC, 7B, and we normally don't have temps below 32 for long periods, 3 or 4 days usually. The coldest that I ever remember was 5 degrees for one morning.

I'm glad I found this forum. This is literally the only thing I found that directly addresses this problem. I knew I couldn't be the only one. Since I switched to using shea body butters, I've been having this issue. After some research, I think I found a solution that has been working so far: Tide Hygienic Clean Heavy 10x Duty Liquid Laundry Detergent & Nature's Miracle Laundry Boost. I chose these two based on reviews that stated how well they work on oil stains. So, I put my clothes on the soak cycle in the washer (using these two products) and let it sit for most of the day (about 6-8 hours) in hot water. Then I wash on the longest cycle in hot water. So far, I have not been getting the white residue after several days like before. I also tried this method with Oxiclean (swapped it for the Nature's Miracle), and it worked pretty well too. A couple of shirts had a small dusting of white residue after a few days that I could easily brush off. Also, I make sure to loosely load my washer; I use around a medium load for a large wash cycle. I'm going to experiment with warm water to see if I can save some energy and help decrease the fading over time. And possibly see if it works without soaking.