Need recommendation on schooling fish

[Shadow]

but that 2 cm different.

[Quixotic]

Is there any website that can give exact accurate length measurements short of measuring ALL the fishes available? I doubt there is one.

Anyway, there are different type of measurements, SL (standard length), TL (total length) and FL (fork length). TL is commonly used as aquarists normally associate measurements with the entire length including the tails.

TL: The greatest length of the whole body between the most anterior point of the body and the most posterior point, in a straight line, not over the curve of the body. Sometimes, when there are two equal lobes, the caudal rays are squeezed together and their tip is taken as the most posterior point (excluding the caudal filaments), or the longest lobe is squeezed to the midline (maximum length or extreme tip length). Also an imaginary line may be drawn between the two lobe tips and length to its mid-point taken as the most posterior point (total auxiliary length or bilobular length). Usually the tip of the most posterior lobe of the fin in normal position is taken as the posteriormost point (total normal length or natural tip length). Total length is used by taxonomists in Myxini, Petromyzontiformes, usually in Elasmobranchii and sometimes in other fishes. Standard length is usually employed with Teleostei. Abbreviated TL.

SL: Standard length, i.e., the length of a fish measured from the tip of the snout to the end of the caudal peduncle, excluding the caudal fin.

FL: Length of a fish measured from the tip of the snout to the posterior end of the middle caudal rays. This measurement is used instead of standard length for fishes on which it is difficult to ascertain the end of the vertebral column, and instead of total length in fish with stiff, forked tail, e.g., tuna. Mostly used in fishery biology and not in systematics.

As you have noticed in Fishbase, the entry of P. simulans mentioned this as the max. length: 2.0 cm SL (male/unsexed; Ref. 38376)

My understanding is that the maximum length is the size (in cm) of the largest male/unsexed or female specimen ever caught. These caught specimens are referenced from published scientific papers. So the above means that based on the quoted reference, the largest fish caught is male/unsexed, 2cm SL. You can lookup Fishbase to find out what the scientific paper 38376 is.

In reality, there are fishes out there that may exceed this length but never caught and analysed. Updates to Fishbase are also based on contributions (note the Comments & Corrections link at the bottom of the species page). Besides that, I think female P. simulans are potentially larger than males. Aquarium bred fishes could grow potentially larger as well.

Bottom line, comparatively, plus minus the fins, sexual dimorphism, etc, the difference in size shouldn't be very much. Therefore, the 4cm TL cited elsewhere is probably 3cm SL actually, so it only differs by 33% from the size in Fishbase.

The above is based on my understanding of interpreting Fishbase entries, so if I got them wrong, please feel free to point out them out.

[Shadow]

yeah you are right, fistly I forgot that female usually bigger. Secondly, it is most likely that farm breed will be bigger than wild breed. I guess this fish is out from my list.

[stream]

after some picture search on the net, I manage to narrow my selection to 3 fishes:

Ruby tetra (Axelrodia riesei) -> 1
Green neon tetra (Paracheirodon simulans) -> 2
Rasbora espei (Trigonostigma espei) -> 3

Where can I get the above fishes nowadays?

[Shadow]

Seaview have it but not all the time, it depend on your luck

[nicholasliao]

I think you can have a look at gold tetras or silver tetras. Im not surr about their scientific name but they usually stick very well to one another