Assessing the effects of urea and TMRL media on laboratory cultivation of Gracilaria corticata

The effects of urea and TMRL media have been surveyed on the laboratory cultivation of Gracilaria corticata during 41 days in spring 2002, using sea water as control. We used nine 25 litre aquariums each containing 100 grams of the red algae. During the experiments, pH, salinity and water temperature were measured daily, airing was conducted continually, and 80% of the water in each aquarium was changed every other day adding the required culture media after the change. Water pH ranged between 8.1 -±0.02 to 9.05 -±0.4, salinity was recorded between 3741 ppm, and temperature range was 24.5±0.49 to 35.3±0.86 degrees centigrade. We measured daily growth rate, net production and final weight of the algae for urea and TMRL culture media which the TMRL culture media provided the highest growth rate and we spotted a change in colour of the algae treated with this medium ranging from dark brown to light brown and colourless phase.