Does size really matter?

[diceman]

Ok Now that I have the females attention, the men can answer too. When ordering or buying a fish I see small medium and large. Is there any advantage to buying a large vs. a small? My thought is that a small fish will live longer because it is so young while a large fish is older and will not live as long. The age thing you know. So wouldn't I be better getting a small watching it get big and get my moneys worth or a large fish because it has survived maybe going through a sickness and now is a stronger fish. Any facts or opinions are fine. OK sorry to disappoint the ladies but yes this was a FISH question.

 

[brooklyn johnny]

Regarding what size is best to purchase, it varies with the species. Generally, "medium" fish are better. This is true with many popular species... angels, butterflies, tangs. The thinking is that very small fish not very established in general, and have a high mortality rate even with the right conditions. Larger fish are so set in their ways and feeding habits it is tough to get them to adapt. So a "medium" fish, depending on the species, is better. This is a general rule obviously.
Regarding age, even "large" fish are relatively young in the aquarium trade. Once again usually, but for the reasons expressed above it is better to stay away from those anyway.
IMO, more important than anything is the individual specimen regardless of size, and that they have adapted well and survived there trip from the far reaches of the planet.

 

[tyrfing]

Okay, let me give you a totally different perspective on it...
I would agree that it's better to go with a medium or smaller size, mainly due to the territory and aggression established in your tank.
If you're adding an aggressive fish, it's always best to add it last, this allows the other animals to stake out territory and defend it. Having "home turf" reduces the stress for your fish. Adding an aggressive fish last reduces encroachment. Now if you add a smaller aggressive fish, many times as these grow (save triggers and eels) they keep their place in the tank and won't bother other fish, even though they could clearly dominate them.
I added a "large" antennate lion (about 6 inches) and he popcorned my cleaner shrimps and hermits. The small Russell's I added left everyone alone, even as he got bigger. He had learned that he had a place in the tank and since he was being fed regularly, he didn't have to go hunting.
The other thing is, add a caveat to your ordering where you specify they call you and get any approvals for substitutions. I haven't orderd from SWF.com (yet) but the previous service I went through substituted sizes without contacting me ("no need to thank us for the free upgrade", aaaccchhhhhh!). I didn't want a medium or large antennate just for the reasons I listed above, but I got one anyway.
Just my 2 cents.
Okay, 3 cents (I do tend to ramble)

 

[fshhub]

one other thing not mentioned,
many species of fish go through stages in growth(which include color and pattern changes), which sometimes they do not in the aquarium, if you want a certain patter, then you should take a look at the fish and then see what you want(maybe you like the juvie look, the fish wil grow, but may not change patterns) and then purchased based upon that(if one of the speciesyou want is like that) and if it does not matter with that particular fish, tehn i would agree with teh above statements and lean towards the medium size when ordering
HTH

 

[tyrfing]

Agreed fshhub. A neon damsel is gorgeous when it's young. As mine got older it became kind of gray green and looked pretty awful

 

[fshhub]

i guess it does work both ways, research will tell you which fish do or dont'
but what i actually meant is that some fishes may not change, and if their adult appearance is what you desire then buy an adult in those cases, or if you desire a juvie appearance, then in that case, buy a juvie, as it will probably remain, but the best thing is to figure out which you want and look into the fish befor eyou buy it, other wise you could be disappointed later on if it does not become what you want, or
in the case like mentioned by tyrfing, you may be disappointed in the outcome when it does change