This is the finished siphon as it starts to work. The water in both tanks will be as close to the same level as possible. If you notice the levels are not the same as it is when the system is running properly check to make sure the tube from the venturi is not restricted. We now use dark tubing to keep alge from growing inside the siphon.

We grow several hundred orchids for our rain forest research. You can use a method we use to check to see if some of the orchids are dry enough to water. By picking up a pot you can feel if the orchid needs water. You can lift each siphon just enough to see if it is full of water. This takes a second, but it can save the day if you notice an empty siphon.

It is best to use two siphons in each tank to make sure at least one is working. That reminds me of the first rule for the coral farmer.

When you enter the farm always listen, look and smell. If everything is not as it always is; find the problem. You can hear if the air pump is on, and you can see if the water in the sumps is at the right level. You can often smell if there is an electrical problem before a ground fault switches off.