Thank you for pics. One of the main considerations when having a saltwater tank will be fish and when there is fish, there is potential for illness, disease, tank and equipment failures. With that, A hospital tank is at some point evident, and we must plan ahead.
I can tell you it sounds complicated but it is a rather easy setup for about $50 and well worth it. It allows easy treatment using very little chemical treatments, allows close up observance of fish and adaptability to display tank after treatment.
As simple as a 10 gallon tank, it requires 22" of space
Tank- $15
simple heater $15
Hang on Power filter - $20 at Wmart
Two PVC pipes 3-4" - $ 5
You can also buy a starter kit at Wmart which has all of the components for about $50
Treatment- at 80 degrees for 15-30 days,,,,,, use copper safe at treatment level 2.25-2.5ppm. To determine level, you will need a reliable test kit and NOT API brand either.
Other option which I DO NOT recommend which is reef safe is to use Polyp Lab medic in addition to ruby Rally Pro for 30 days but Medic is a peroxide salt only and does Not always work and furthermore, what you spend on Medic and Rally, you will spend the same for a Quarantine setup that will last you a lifetime.