Tacoma, you need to find a new dive service. The one you have is either incompetent or is lying to you. Or both:

1.- It is not possible that you had "no growth" in a 3 week period. Further, a 3-month frequency in San Diego is not a best management practice, it is a worst management practice. That your service would go along with this is indicative of their professionalism, or lack thereof.

2.- The Port has not instituted any rules regarding hull cleaning frequencies.

3.- The Port have banned creating a "plume" of color in the water during hull cleaning. If this is occurring with your current service, they are in violation and should be reported.

4.- All hull cleaners must have the Port permit to work on Port property. You might want to ask to see theirs. They may be trying to fly under the radar.