Surge protection and lightning arrestors are similar but different animals. Surges are generally caused by glitchs in the grid that can cause spikes or dips in voltage that can cause damage. Apc batt. computer back up units are made for these type problems. Check with the warrantee on the apc's. Especially the at service unit. They usually come with an insurance type protection. The pricier ones say they will replace damaged electronics etc. up to a certain dollar amount if they fail to work as advertised, but need to be the lightning arrestor type. Check with your home owners policy. They also will cover part of the cost of loss for lightning strikes. Surprised about the ehiem. I would have expected a potential problem with the electronic controlled one only. Lightning does not always obey the rules so to be fully protected you should use an arrestor at your service and also at the point of use, and anything using a wire be it phone, catv, sat., or power should have a point of use protector. That's the problem miss one or have a low grade type and you are at risk. The higher the "joule" rating the better and more expensive the unit.