With tanks there are a lot of things that can be considered risky business, like introducing fish without quarantining them, eyeballing dosages, or adding in things to your tank without dipping or knowing where they came from (wild rock, random coral frags or colonies), or filling a 2ndhand tank inside without water testing it first. We all do things like this from time to time especially when you're getting started in the hobby. What would you say is the biggest risk you have taken, and were there any consequences?
