If you need a great DIY auto top off device, then you might want to look at this clever invention. The auto top off uses a Sun Tea jar, and a air tube that fills the tank automatically. How does it work? It uses water & air pressure. Originally popular back in 2005, this device still has practical application today if you need a cheap auto top off system. Follow the break below for the full how to by Greenuku.
Sun Tea Jar Auto Top-off
我答应在夏季初，我会以廉价的重力喂养自动售价来发布操作方法。好吧，夏天比预期的要忙碌，如果您像我这样的懒惰，那是旁观项目的死亡（甚至是这样的简单）。无论如何，这是我的操作方法和关于Sun Tea Jar Auto顶级的讨论：
什么，如何和原因：
This auto top-off is gravity fed and controlled by pressure (no pumps or float switches). I don’t know if there is a good, catchy name for it, but it doesn’t seem to be a very popular type of auto top-off, even though it is arguably better than the float switch type for smallish tanks. That’s why I thought I’d post plans for a cheap, easy version.
这种顶级的工作方式非常简单。空气入口管放置在所需的水管的水平上。滴管将淡水放回水箱中。当水位到达空气管管时，水会防止空气进入容器和滴水站。实际上，实际上将水吸入空气管，直到上升到容器中的压力相互抵消的水平。当足够的水箱水蒸发时，水位掉落在空气进气管下方，将空气放入容器中，然后再次开始。
I’ve been using a similar top-off on my main system for about a year and have had very few problems. Here are what I see as advantages (over other auto top-offs):
- Cheap (this one cost me about$ 10, though fancier versions can use some expensive parts)
- Very low maintenance
- Relatively failsafe (no moving parts)
- 工作（自动维护您的水位）
具体而言，我构建的这个版本非常便宜，（相对）易于查找零件。（稍后再详细介绍。）
部分：
- Glass sun tea jar with plastic lid ($4 at the grocery store, a seasonal item)
- 1/4 inch (outer diameter) tubing (standard airline tubing, I got 20 feet of vinyl tubing for less than $2 at Home Depot)
- 3/8英寸（外径）油管（25英尺的聚乙烯管在Home Depot的25英尺$ 4）
- Number 4 rubber stopper ($1 at a chemistry supply store)
- 有机硅水族箱密封剂（小管为几美元[〜$ 3]）
There are a number of reasons I went with the glass sun tea jar. For this top-off to work the container needs to be非常僵硬。除了便宜之外，Sun Tea Jar还很僵硬，在底部预先钻出，甚至还带有自己的舱壁（排序）。不幸的是，Sun Tea Jars似乎只在我去过的每个地方都出售。我一年前要使用一个，但是我等了太久了，他们不再出售。
DIY
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[*]看到了齿轮的末端，因此只有一个孔被暴露出来。
[*]将一块3/8英寸的油管插入“舱壁”中。最后，我不得不稍微刮下管道，但后来它进去了，提供了紧密的合身。这部分将充当“适配器”。
[*]将1/4英寸管的末端放入3/8英寸管道的末端。我的依恋。如果没有，您可以硅胶。
[*]在盖子的顶部打一个孔，以进行3/8英寸的管道。我实际上是手动的小钻头，然后用剪刀扩大了孔。不是很喜欢，但是奏效了。
[*]Insert the 3/8 inch tubing into the hole.
[*]重要的是：整个容器必须绝对密闭。
*将硅胶密封剂放在盖子两侧的3/8英寸油管周围。
* Put sealant on the hinges of the handle (on the inside of the lid).
* Put sealant on the inside rim of the lid and carefully screw onto jar.
[*]After the sealant cures (at least a day), mount the 3/8 inch tube so that its tip is at the level where water should be. Mounting can be tricky. I suggest doing something with plastic cable ties.
[*]将1/4英寸的管子放入可以滴入水箱中。管道中的结可以将流量限制在您想要的任何速度上。
[*]用淡水填充太阳茶罐，将塞子牢固地放入盖子的填充孔中，然后开始测试。
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我建议让您的“测试箱”至少一周的“测试箱”上的一流。设置中的任何空气泄漏或堵塞都可能导致水位逐渐变化，要么太低或太高。
Considerations
As I said before, sun tea jars are generally a seasonal item, so it might not be easy to find one if it isn’t summer. On my main tank I built a very similar top-off with an acrylic jar/canister that was sold as packaging for pasta. In any event, the container you use needs to beRIGID!
The reason for the 3/8 inch tubing as the air inlet, is that water will just stay in tube of smaller diameter due to surface tension, not letting the drip restart.
I have noticed that when the water level drops and air first enters the inlet tube, some tank water is sucked into the container. Over time, this leads to a lot of algae bits and such ending up in the container. If this happens, you should occasionally flush the container with fresh water, which may entail removing the drip tubing.
更强大的设计可能会涉及橡皮塞以外的其他东西（我的另一个最高卫星有球阀）和易于发掘的管，以进行清洁或更换。另外，您可以考虑使用静脉输液器，而不仅仅是航空管，以更好地控制滴水速率。
Note that in my pictures I was using a 1/4 inch tube as the air inlet, but I discovered that the tubing was in fact too narrow.
