There are 4 cone morphologies in zebrafish, corresponding to UV (U), blue (B), green (G) and red (R)-sensing types, yet genetically, 8 cone opsins are expressed. How 8 opsins are physiologically siloed in 4 cone types is not well understood, and in larvae, cone physiological spectral peaks are unstudied. We use a spectral model to infer cone wavelength peaks, semi-saturation irradiances, and saturation amplitudes from ERG datasets composed of multi-wavelength, multi-irradiance, Aspartate-isolated, cone-PIII signals, as compiled from many 5–12-day larval, and 8–18-month adult eyes isolated from WT or roy orbeson (roy) strains. Analysis suggests (in nm) a 7-cone, U-360 / B1–427 / B2–440 / G1–460 / G3–476 /R1–575 / R2–556 spectral physiology in WT larvae, but a 6-cone, U-349 / B1–414 / G3–483 / G4–495 / R1–572 / R2–556 structure in WT adults. In the roy larvae there is a 5-cone structure: U-373 / B2–440 / G1–460 / R1–575 / R2–556; in roy adults, a 4-cone structure, B1–410 / G3–482 / R1–571 / R2–556. Existence of multiple B, G, and R types is inferred from shifts in peaks with red or blue backgrounds. Cones were either high or low semi-saturation types. The more sensitive, low semi-saturation types included U, B1 and G1 cones [3.0–3.6 log(quanta·μm−2·s−1)]. The less sensitive, high semi-saturation types were B2, G3, G4, R1 and R2 types [4.3–4.7 log(quanta·μm−2·s−1)]. In both WT and roy, U- and B- cone saturation amplitudes were greater in larvae than adults, while G-cone saturation levels were greater in adults. R-cone maximal amplitudes were the largest (50–60% of maximal dataset amplitudes), and constant throughout development. WT and roy larvae differed in cone sisgnal levels, with lesser UV- and greater G-cone amplitudes occurring in roy, indicating strain variation in physiological development of cone signals. These physiological measures of cone types suggest chromatic processing in zebrafish involves at least 4–7 spectral-signal processing pools.