Internal factors are factors that affect the growth of seaweed in the body itself. Internal factors that affect the growth of seaweed include:
Type of seaweed that has been widely cultivated in brackish waters is Gracilaria sp. Gracilaria also have some kind of nice to be cultivated among others Gracilaria verucosa, Gracilaria eucheumoides, and Gracilaria folifera. But these three Gracilaria is somewhat difficult to distinguish, so many people know him by Gracilaria sp. or as the name of each area like that or dongi-dongi.
Figure 1. Seaweed Gracilaria (a) Gracilaria verucosa, (b) Gracilaria eucheumoides, and (c) Gracilaria folifera
As for the seaweed that has been widely cultivated in the sea is of the type Kappaphycus and Eucheuma. Some experts seaweed has made a deal to classify the type of seaweed that has the same taxonomic namely Phylum Rhodophyta, Rhodophyceae Class, Subclass Florideophycidae, Gigartinales Order, Family Areschougiaceae, Tribe Eucheumatoideae, of Tribe Eucheumatoideae grouped into three types, namely Betaphycus spp seaweed, Eucheuma spp and spp Kappaphycus the third is a source of carrageenan.
Kappaphycus and Eucheuma since 1970 becoming a major source of carrageenan producer to industry so that more cultivated. Kappaphycus alvarezii has the trade name “cottonii”, Kappaphycus striatum has the trade name “sacol”, Eucheuma gelatinae under the trade name “gelatinae” and Eucheuma denticulatum has the trade name “spinosum”, three types of seaweed producer of carrageenan is what has been widely cultivated and widespread around the world. the real difference of the three types is presented in Table 1 below.
Table 1. Differences type Eucheuma and Kappahycus
Eucheuma denticulatum have a common characteristic thallus cylindrical, smooth, dark brown color, green-brown, green, yellow or red purple. special features morphologically, this type has the thorns that grow rows encircling thallus. Eucheuma denticulatum grew in almost all Indonesian waters.
Figure 2. (a) Kappaphycus alvarezii (cottonii), (b) Eucheuma denticulatum (spinosum) and (c) Kappaphycus striatum (striatum / sacol)
Zucarello et al., (2006) stated that Kappaphycus and Eucheuma very difficult to distinguish because it has characteristics similar morphology, supported by growing seaweed cultivation of both types of seaweed that has undergone domestication. thus distinguishing from Kappaphycus types can be seen from strainnya that has characters that can be used to identify the type of seaweed.