The effect of the epiphytes of Chaetomorpha crassa on the total chlorophyll-a and growth of Gracilaria verrucosa

Gracilaria belongs to the class of red algae (Rhodophyta), it has many subtypes with different morphology and anatomy. The epiphytes that often attack Gracilaria are Chaetomorpha crassa epiphytes; they trap Gracilaria and have a negative effect such as nutrient competition, inhibiting the light penetration and reducing the growth rate. The purpose of this study was to determine the effect of Chaetomorpha crassa epiphytes on the amount of chlorophyll-a and the growth of Gracilaria verrucosa. The treatment used was an epiphyte mass of Chaetomorpha crassa by as much as 0% (control), 25%, 50%, 75% and 100% of the mass of Gracilaria verrucosa. The analysis of the data used Analysis of Variants (ANOVA) and continued with further tests using Duncan's multiple range test. The results showed that Chaetomorpha crassa had no effect on the amount of chlorophyll-a, but that it affected the absolute weight growth and daily growth rate. The amount of chlorophyll-a, absolute weight growth, daily growth rate, and best long growth were obtained in treatment A (control). The amount of chlorophyll-a, absolute weight growth, and daily growth rate was 0.3110 μg / ml, 0.93 gram, and 1.68% per day respectively.