A few weeks after setting up the tank, I noticed that the lower end of the cabinet looked dark and wet. To make a long story short, I had not properly tightened one of the 1" bulkheads that serve as overflows in my sumps. This resulted in a slow leak and about 30G per day of water in the cabinet. Unfortunately I noticed the problem only after several days. They cabinet held up remarkably well, but even when fully dry, the dark color around the bottom remained, so that I bought a wooden baseboard from a hardware store and covered that area.

This episode taught me that I needed instant notice if water was gathering in the cabinet below my sump containers. So I went ahead and bought a Coralife The Screamer. This is a battery operated water alarm, which has a senor consisting of two metal prongs. If electrical contact is made between these tow prongs, for example by them dipping in the same puddle of water, an ear piercing alarm will sound.

To work for my application, the sensor needed to be installed strategically at the lowest point of the cabinet below the sump containers. The standard sensor did not ft in this space, but fortunately it was no problem to connect The Screamer to two bare pieces of wire. These now lie underneath both of my sumps, and the alarm will sound if there is enough water in that space to bridge the wires.

The Screamer typically retails for $17.99, but at the time of writing seems to be sold out in many of the reputable online aquarium supply stores. I just did a search of eBay for water alarm and there seem to be a number of devices available, which essentially do the same thing as The Screamer, but some of whom are a good deal cheaper. Of course I have not tried any of these, and can not give any specific recommendations.