[mike31154]

Welcome to the forum & the salt water community. Take your time, keep researching & get your budget ready for a bit of a hit initially & some continuing expenditures over time.

With respect to lighting, advances in this technology, particulary the advent of suitable LEDs for the hobby have pretty much made the watts per gallon rule of thumb obsolete. You really need to look specifically at each technology and match it to what your ultimate goal is. Each type of lighting produces a different ratio of lumens per watt. I would recommend, if you have the budget, try to go for LEDs right from the start, particularly for the smaller system you are planning. They use less power & provide more flexibility as to configuration as any other current technology offered in our hobby. You should have little trouble getting plenty of coverage at a reasonable price with LEDs on a 22 gal.

The Koralia will be a good start, but you may require additional flow as the system takes shape. No worries there, this can always be added. There are some innovative new products out there for flow as well these days. EcoTech VorTech & Tunze are major players, more costly than most, but also durable & offering plenty of options.

Live rock, sumps & skimmers are the mainstay of most marine systems these days. There are successful, nice looking system that run sumpless & without skimmers, but it's probably not a good way for a novice to start. If you have room for a sump, that can be a great addition to provide extra water volume and house equipment such as heaters/skimmer so that your display may be kept free of these items. HOB filter is fine, can act as a sort of refugium as well if you decide to go sumpless.

A couple of other things you might find helpful, an RODI system for pure water & some sort of top off system to compensate for evaporation.

I believe there are a few 'sticky' threads in the forum that will answer many of your initial questions as well. Have a look around & I'm sure you'll find plenty of great info to make the entry into the hobby smooth & relatively painless.