The photosynthetic system of brown algae is made of a P700 complex containing chlorophyll a. Their plastids also contain chlorophyll c and carotenoids (the most widespread of those being fucoxanthin). Brown algae produce a specific type of tannin called phlorotannins in higher amounts than red algae do.

Do all algae photosynthesize?

Photosynthesis is the process by which light energy is converted to chemical energy whereby carbon dioxide and water are converted into organic molecules. The process occurs in almost all algae, and in fact much of what is known about photosynthesis was first discovered by studying the green alga Chlorella.

Is brown algae non photosynthetic?

The groups that are sometimes associated with them include the 'golden-brown' algae, the brown algae, and some non-photosynthetic forms, in particular the water molds (Oomycota).