Steve, know the feeling I'm creeping up on your age, just 4 years behind
. Of course I understand that you are not flamming me and entitled to your opinions and vice versa as we all see things differently.
Asking tough questions and I will stick my neck out on the chopping block
.
1: This is true as most angels are expensive, but there are cheap & very delicate angels ~ Singapore angel, that require the swimming space. You are correct
with regard to price as most people are buying on impulse / cost. Additional factor is that Tangs are generally more gregarious then angels and quickly catch the attention of buyers. This also ties into my comment about the ability to chose a healthy fish.
2: Bring in the proverbial "shark egg" issue
. What to do with any fish that has outgrown its environment is a tough one....just as taking back a fish thats too aggressive for your tank to the lfs and subjected to associated problems. But lfs is one place to exchange fish, friends with larger tanks, local public aquariums, etc.. Its tough to answer and leads to a nasty repetitive circle. Just saying that the enjoyment of keeping tangs/angels can be done in smaller tanks. Shark eggs should only be kept by experienced aquarists living next to that species natural environment.
3: No not really since both marine and fresh fish will become stunted in tanks. Some species will become deformed, some stressed, and the majority adapt to their new environment leading healthy lives. Just trying to point out that the fish are not going to out grow their tanks within a very short timeframe. Majority of the aquarium maintained fishes are generally subjected to other factors that contribute to stunting, overgrowth and / or environmental stress just from captivity
4: I was only giving my interpretation of various postings of certain tang species per volume of water. In 300 gallons you could easily keep a few tangs fat & happy!.
Just trying to show that tangs can be maintained in smaller volumes of water, living healthy lives and providing enjoyment to their owners.
I understand your point very well, maybe even more since I considered quite a few more fish families that are unsuitable for aquariums. But I also realize that we like to maintain these beautiful critters to the best of our abilities, and tank size for most tangs or angels is a minor concern against water parameters, filtration capacity, etc.
Not even going to get involved in that can of worms regarding fish & feelings, leading to why keep fish captive, water volume as the cows will be awfull fat by the time they come in from pasture
.
Joe