Part of a Flickr album www.flickr.com/photos/greenscaper/sets/72157646460535762/ Also see this blog post at InsideUrbanGreen.org www.insideurbangreen.org/2014/09/a-sub-irrigated-bubble-s... This would be my entry for the simplest sub-irrigation planter (SIP) contest. It fills a huge SIP niche because you can use this plumbing in any watertight container. You do not need to sacrifice the look you like on your patio, balcony or roof. Move plants around at will to suit your fancy or seasonal change. The 2-bucket SIPs are somewhat ugly and the EarthBox and its DIY knock-offs are often over engineered by the tool-guys. I named them “bubble SIPs”. They are not really SIPs (as in planters), they are the simple plumbing to make a SIP from any water-tight vessel. There is nothing high tech or exotic about bubble SIP plumbing. As you can see, it is very simple. The fill-tube connects to the water and oxygen reservoir connects to the overflow drain valve. That's it! I call them "bubble SIPs" because the plant(s) are in fact sitting on a bubble of water and air. Add adequate light and it doesn't get any better for optimum plant grow while saving about 70% of the water typically used for traditional "drench and drain" top watering. It is a very simple form of hydroponics without the need for an electric pump for oxygenation. The ebb and flow action in the reservoir provides the necessary oxygen. I might add that hydroponic stores knock this method because they do not make any money with it. Please stop using those drain hole pots. You are wasting precious water, time and plants that die from either over or under watering. Contrary to what the "master gardener" and gardening writer crowd tells you, there is absolutely no need for traditional drain hole pots. Unfortunately, water-wasting drain-hole clay pots are ubiquitous much to the detriment of the environment. The water/oxygen reservoir in this case is a 48 oz plastic food container (Glad or equivalent). Rather than using a drill, I use a wood-burning "pen" to poke the small (approx. 1/8") air holes and the holes for the fill tube and overflow valve. The overflow valve is 1/2" o.d. vinyl tubing. The barrel of the wood-burning pen is about the same diameter. Simply push the pen tip until you reach the barrel and it will make nice 1/2" holes. You need one for connecting to the reservoir and one to exit out of the planter. It works great for plastic and composite planters. Ceramic and clay pots are another story. Drilling holes in them is extremely difficult. I engineered a method that requires no drilling. You can use a traditional pot with a drain hole at the bottom. See this photo. All of the SIPs I make have fill tubes made from recycled water bottles. Most of them require an attachment hole of about 1" or so diameter. Push the hot pen through to the barrel and rotate the pen to make a larger hole. The hot pen barrel will melt the thin plastic very quickly. It takes just a little practice to get the hang of it. To fill the water/oxygen reservoir, simply pour water into the fill tube until you see some water coming out of the overflow drain valve in the side of the SIP. The overflow valve is also a drain for excess water when it rains. Of course, there is not much need for that at this time of the drought crisis here in California. The drought is even more reason for growing all of your plants whether decorative or edible in water-conserving SIPs. Both you and your plants will love the results.