40G Nuvo AIO
Space is always a factor. I have two tanks, a 32 AIO and a 65 with a sump below. I've learned the hard way, and now I QT everything. Since I only introduce small fish in my systems but mostly corals, I use an AIO 5 gallon EVO peninsula tank. Light and everything is about $100 and I use one of my spare heaters. When something is coming in, I setup the tank with water from the larger system (and replace with a water change in the original system). Add a rock from the target system for filtration. If it's just for corals, I go with that and do weekly water changes until I'm ready to add to one of the other tanks. I also have carbon in the tank because the chemical wars continue. If I get a fish I will cycle the small tank with stability and monitor it, then add the new fish or invert and add an ammonia badge just in case. I sit this on my home office desk and break it down when done. Works great for me. And for corals I can have this up and running quickly (just in case I came across something that was a must have). All I need is to mix and heat the 5 gallons of saltwater that replaced the source water in my larger system and the tank is up and running.