200 Gallon! Geez, I've got a 55gal and that's big enough for me! Would love a tang but there's insufficient room and it'd be unfair. I've currently got 2 clowns, a blue damsel, a cleaner and fire shrimp and an urchin, along with the standard cleanup crew.
So far so good, levels are stable and no casualties thus far!
Just take your time, it should take a year or more to get upto full capacity but there will be plenty of changes taking place in your tank to keep you interested. Wait until the coraline starts to go grow, you'll have pretty stable conditions when that happens.
The biggest killer of fish and inverts is stress, any changes should be made slowly. Stress can kill outright or lead to disease, which causes more stress, which causes more disease, a vicious circle. Once you get a tank right though, it's pretty easy to maintain and not too time consuming as can sometimes be perceived. If all is well, you should only need to make water changes periodically and not interfere too much, if it ain't broke, don't fix it.
I've had a few tangs in my time, the podwer blue in the pic above was a stunner, had him over 5 years, he survived my move to Scotland. You need very stable and good conditions for tangs though, they don't do stress well. Below, my 7x2x2 as it progressed but a move to a smaller bungalow resulted in me breaking it down and selling it, a sad day.
I currently have a 26 gallow FW tank with a pair of firemouths in and a small nano reef, with a perc and cleaner shrimp in. The biggest factor for me not getting a bigger tank again is expense, it's not a cheap hobby and my photography tends to suck up my pocket money these days.
Sorry for the pants pics.
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