Diving in KelpMonterey has beautiful kelp forests, but they require specialized knowledge. There's no Kelp Monster, the kelp isn't going to attack you, but if you aren't careful, you can feel that way.
The fish live in the kelp, but they never get tangled in it because they are streamlined. The same shape that let them slip through the water lets them slip through the kelp. You should emulate a fish.
Secure all loose gear. That dangling octopus or computer should be stowed so it doesn't catch.
Some folks turn their first stage over so that the low pressure side is below the high pressure side. You may find this restricts your head movement but it's worth a try. You can always change it back.
Duct tape your fin straps or, better, put an inch of bicycle inner tube on the them, so they don't snag the kelp. Duct tape is easier, but it's ugly, and needs to be replaced every twenty five dives or so. If you cut a one inch section of old road bike inner tube and stretch it over the ends of the straps, it will generally outlast the fin straps. <<Picture>> Another alternative that works on older fins that don't have fancy quick release buckles is to put the strap through the buckle backwards so the loose end of the strap is between your foot and the rest of the strap. And spring heels are generally pretty snag-proof.
If you find yourself finning like crazy and not going anywhere, stop, take a second, and find the strand you snagged and unsnag it.
If in spite of doing all this, you snag some kelp, just relax and unsnag it. Frequently, just rolling your body to check on the snag will be enough to unsnag it. If you do manage to get yourself all wrapped up in a kelp stole, remember that the kelp will break like a carrot if you bend it. In a pinch, you can bit through it easier than a celery stalk.
Most importantly, don't swim through the thickest part of the kelp, swim a few feet to the side and go around it. And remember that the kelp strands will break like a carrot if you bend them sharply in two, or you can bite through them.
You don't want to be out of air in the middle of a kelp bed. Plan on being on the surface with 500 to 800 psi to swim back to the boat underwater. Crawling over the top of the kelp is not a fun experience. It's very strenuous and embarrassing. The process works like this:
Navigation skills are important so that you surface near the boat or the exit point. I set the lubber line on the compass to match the way the anchor line is pointing, and just visualize where I am relative to the boat. And note the depth that the anchor is in -- it's a lot easier to find the anchor by swimming along a depth contour.
Taking a boat into kelp is generally a bad idea, both for the boat and the kelp. The prop will chop up the kelp. The kelp will get it's revenge by snagging on the lower unit of the motor and can cover the cooling water intakes causing an overheating situation. I usually put the motor up while I'm diving so if the wind changes direction, the boat will drift over the top of kelp rather than getting tangled in it, and I can then use the anchor line to pull the boat back out of the kelp bed.
It's a bad idea to deliberately go charging across a kelp bed with your boat. I've had to do it a couple of times in a rescue situation, but I've come to the conclusion that it's generally better to send a free diver in if there's time. If you have to go in, put your motor up as far as you can and still get cooling water and keep the prop in, and take a running start at it. As you hit the edge of the kelp bed, turn off the engine and put the engine all the way up, and coast in. This, of course, requires an engine with power tilt. Don't run the distressed diver over.
An audible overheat alarm is a very good idea even if you never go in the kelp beds. This is important even if you keep the boat out of the kelp beds. I know one fellow who blew his outboard when he picked up a frond of drift kelp across the intakes. The power head rebuild cost several $K. My overheat alarm has gone off a couple of times due to drift kelp. I've been thinking of installing a water pressure alarm. That would react to a blockage more quickly than the temperature alarm.