build your own oasis

So this looks cool, and you're thinking how do I build my own inexpensive inflatable tub?

Here's a high-level overview of the parts list I used.

• The Tub: I have the Coleman 2017 model. It looks like they're updating it for 2018, a little bigger and more refined. The tub is actually made by Bestway Here's the link http://www.bestwaycorp.us/Product/ProductForm?productId=4239 the Coleman model can be had on Amazon for around $350 delivered. It comes with an integrated Pump/heater/blower and rudimentary timer function built into the "Egg" unit. There is nothing wrong with it at all. If you don't mind the extremely inefficient heater stop here, you don't really need Oasis Spa. It takes days for the water to heat, and don't ever turn it off, the heater will take hours and hours to heat back up again. There is also a Water Jetted model.. hmmm
• Raspberry: The Pi if you already have one, use it. Otherwise this was the current model when I started the project. The Oasis Spa OS release images have been compressed and minified. But don't be cheap, use at least a 16gb class 10 micro SD card. Once you get everything all dialed in, shut it down and create yourself a backup image of your Oasis Spa OS SD card. Don't skip this, SD cards die.
• Switches/Relays: Sonoff SV for low voltage lights/heater use.
• Buck converter: Voltage manipulation I use a single 18v DC power supply. The output is wired to the Buck Converters to get the desired voltage to the individual SV units. For example, the Lights take 12v and the Heater takes 2x alkaline batteries at 3v. The buck converter steps-down the voltage correctly.
• Sensor Switch: Sonoff TH10
• DS18B20: Sonoff Sensor Wire and extension cable if needed
• Heater: Outdoor Propane Tankless Heater
• Pump: Water Pump
• Hoses: Potable garden hose I use these for the water in/out of the tub to the heater. High quality drinking water safe. A few feet of 1" clear vinyl tubing from the hardware store. This is for converting from the 1" pump input/output, to the garden hose.
• Fittings: can't even count.. all kinds of 3/4" and GHT gender changers, fittings, bits, bobs and a good roll of wire and some cut extension cords for wiring the 110v stuff. If you're stuck, ask. A good place to start is Banjo Fittings. They have nearly everything needed and available on Amazon. This is really important, with water flow don't convert down in size. Try to keep everything at garden hose size. 3/4" OD 5/8" ID pic. Conveniently, the Tub and the Egg use garden hose connections. Also, try to stay away from metallic fittings. Plastic/Nylon is best for this stuff.
• Protection: My setup lives outside. I protect the power cables with these things. As well as a wall-mounted outdoor electrics cabinet, DIY. Also, the large size fits the Pump perfectly. I cut holes in it to feed the 1" tubing through. Keeps pump protected perfectly. pic