All surfaces of the tripod frames, current sensors, and some instrument cases were painted with antifouling paint (Pettit Marine Paint Trinidad Anti-fouling, Cuprous Oxide 65%, Inerts 35%, EPA reg. #60061-49). In general, this was effective at minimizing fouling over the 5-month deployment.
The optical windows of the transmissometers were affected by some biological growth. The windows of the transmissometers were surrounded by a porous plastic ring impregnated, using a vacuum technique, with Controlled Environmental Chemical Antifouling Protection (CECAP, manufactured by Oceanographic Industries) which contains trialkyltin (Strahle and others, 1994). The toxin slowly leached into the water in front of the transmissometer window to retard the growth of barnacles. Although this protection discouraged macrofaunal growth, accumulation of algal slime on the transmissometer windows continued to gradually blocked light transmission, resulting in a gradual upward drift of the beam attenuation coefficient. For example see the increase in beam attenuation at site B during the last month of the deployment . The beam attenuation data have not been corrected for biological fouling and should be interpreted with care.
The ports for all of the conductivity cells (on SEACAT's, MicroCAT's, and on the bottom tripod systems) were fitted with hollow porous plastic tips impregnated with trialkyltin, to reduce fouling (Oceanographic Industries). The conductivity cells are sometimes affected by a slow, gradual buildup of a biological film on the electrodes and also occasional sudden deposits of material inside the measurement volume of the conductivity cell. Seabird pumps were used on the bottom tripod system to flush the conductivity cell prior to making a measurement, reducing the effect of deposits on the conductivity measurements. Salinities are reported as measured and have not been corrected for possible fouling errors.