I found an old tank at my dad's house. He and my uncle used to hate seeing a water line and added a strip of electrical tape just under the rim. I'm not sure why they didn't just add water to the rim. This tape has been on there for 10 years or better and I wanted it off now there is a terrible residue on the outside of the glass. Just wondering what the safest and most effictive way to remove the gunk from the tank. I'm in no real hurry to fill it as I'm not sure if I'm go high-tech or low-tech dirt.
Tank 30g Long Lights 36in Coralife T5 2 21 watt 6700K/Colormax Filter AquaClear 50 Substrate Gravel Ferts Florish
Whatever you use, plenty of wash and rinse afterwards.
Though on the outside of the tank is less worry than on the inside. Still, I would make sure it is clean. Goo Gone and related products can be very effective. Just make sure they are completely removed when the job is done.