a. Algae Ectocarpus
Ectocarpus sp. is one type of brown algae (Phaeophyceae). Brown algae commonly found in the sea, attached to the rocks and often stranded on the beach. Body shape resembles a higher plants because it has a tool similar roots, stems and leaves. Thallusnya length can reach 10 meters. The brown algae contain chlorophyll because in addition also contain pigments fukosantin which is dominant and carotene pigments and santofil.
The way we recognize this plant on the coast is by observing their characteristics, such as brown thallus that has air bubbles. These air bubbles can cause brown algae float in seawater. The air bubbles also contain a reserve of air to breathe. Brown algae reproduce vegetatively by fragmentation and multiply generative with Oogami namely smelting spermatozoon and the ovum to form a zygote.
Then the zygote will grow and develop into mature brown algae. This algae if grown side by side with seaweed cultivation will lead to competition in terms of utilization of nutrients and dissolved oxygen. These pests are found in cultivation in ponds.
b. Alga Enteromorpha
Enteromorpha sp. comes from the word meaning enteron intestine and morphe meaning shape. Middle and end cell contains one pirenoid in each cell. Chloroplast often has a bowl that looked at the surface of different sizes in length in each cell. The shape and arrangement of cells such as in higher plants. This algae is small and often form clumps.
Thallusnya tubular and in it there is the cylinder chamber. Life cycle experienced turnover offspring isomorphic, but some species are only using zoospores in reproduction. Zoospores liberated through the lateral hole in the cell wall. This algae is used for fish food (Aslan, 1991). These algae are also commonly found on the cultivation of Gracilaria ditambak, as a competitor of nutrients and dissolved oxygen.
Figure 23. Hama macro Gracilaria grown in ponds (a) Ectocarpus sp. and (b) Enteromorpha sp.