In the COMPACT version of the PHYTO-PAM-II all components including the measurement chamber are enclosed in a single compact housing. Thus, during normal operation, the only cable that needs to be connected is the USB cable for communication with the PC. It makes this device particularly suitable for use on deck and in the field.

In addition to fluorescence-based determination of chlorophyll content, the PHYTO-PAM-II provides comprehensive PAM saturation pulse analysis for differential assessment of photosynthetic performance of four algal groups within one sample. Also, a fast kinetic mode for the determination of the wavelength-dependent absorption cross section of PS II, σII(λ) is provided for analysis of the samples (non-devonvoluted).

The compact unit can be equipped with the Flow-Through Cuvette PHYTO-II/FT. Together with the 0-10 V Universal Pump Control PHYTO-II/FT/I, common laboratory peristaltic pumps can be used for software controlled automated sampling.

The COMPACT version of the PHYTO-PAM-II features a 15 mm (outer Φ) round cuvette, which is illuminated from the bottom, with fluorescence being detected at a right angle. In this way, the entire sample is illuminated homogeneously, and a representative part of the sample is monitored.

In PHYTO-PAM-II instruments, reference spectra measured with dilute suspensions of pure cultures, corresponding to 5-point fluorescence excitation spectra, are used for automated online deconvolution of up to 4 classes of phytoplankton having different types of pigment in their antennae (green algae, diatoms/dinoflagellates, cyanobacteria and phycoerythrin containing organisms, like cryptophytes). All data can be recalculated at any later time with other references.