Neon tetra
Freshwater angelfishWhere do SL and TL end?
Standard length (SL) measures from the snout to the tail-fin base region and excludes the caudal fin. Total length (TL) includes that fin. Tail position and endpoints can differ between protocols, so check the original method. These are straight-line measurements, not distances traced along a curved body.
Can you compare two figures labelled 5 cm?
The number alone is insufficient: 5 cm SL and 5 cm TL end at different points. Keep measurements separate unless a reliable conversion for that species is available; do not add an arbitrary percentage to SL.
Read the unit, measurement type and description of the fish. Was it a juvenile, adult, male, female or domestic form? A source that says only “5 cm” has not necessarily reported total length.
A maximum record is not a typical adult size
FishBase distinguishes the largest reported specimen from its common-length field. A maximum can highlight a long-term space concern, but it does not establish the usual adult size of every aquarium specimen.
Where a reliable typical adult range is unavailable, this atlas keeps it unknown. That does not mean the fish stops growing: it means a record ceiling has not been substituted for an ordinary adult range.
What else do you need before choosing a tank?
This guide explains measurements; it does not provide a tank-size multiplier. A length alone does not describe body height, swimming behaviour, social requirements or territorial behaviour. Check those in the species profile before making a space decision.
Use the linked neon tetra and freshwater angelfish profiles as reading exercises: find the measurement label, then check space notes and unknowns. Their inclusion here is not a recommendation to keep them together.
A gallery picture is not a ruler
Gallery images are fitted to similar display areas so you can examine their appearance. Two equally large pictures do not imply equally large fish. The PeekFish aquarium is a visual preview; illustration dimensions and verified biological measurements are separate. Its appearance does not establish stocking capacity or compatibility.