You've laid down the cash and are the proud owner of an underwater video system. Shiny and unscathed, it comes to you perfect, ready to control and protect your camera. How well it keeps your camera safe however, is up to you and how you maintain it. In this article I'll go over all the essentials you need to know to keep your o-rings clear, the water out of your housing and your electrical contacts clean.
An o-ring is the only thing sitting between your camera and the ocean and thus your entire housing boils down to little more than how well cleaned and seated these o-rings are.
Housings have o-rings every place there is a lever or button intruding into the housing. These o-rings will be maintained through annual services at a service center. Not by you. The only o-rings you'll need to continually maintain are the rear-plate and front port o-rings.
In a clean place before the dive, take off the front port and back plate and visually inspect them. Look for eyelashes, nicks, sand...anything that may cause a flood. If doing repetitive dives from a boat try not to remove your back plate or port. The speck of dust causing a flood will not work its way into an o-ring seal, but fall onto an o-ring when the housing is open. After your dive day is over, you can once again take your camera out of its housing to clean anything that may have invaded during the day.
I don't recommend removing o-rings just because a dive day has passed. Each time you remove an o-ring, you risk damaging it. Use your better judgment. If you've spent a day doing sandy shore dives a cleaning is probably in order. If boat diving, be vigilant in your visual inspections and use your better judgment to decide if a cleaning is in order.
When you do decide your o-rings need to be removed and cleaned this is what I recommend you do.
Set a cloth next to you as a clean place to set your o-rings.
Remove the o-rings by pinching the o-ring together into a loop. Carefully remove the o ring. Or, use a tool or credit card to slide underneath the o-ring. When using a tool be careful. You can easily nick your o-ring this way.
Once your o-ring is removed, gently wipe it with a lint free cloth to remove any large particles.
Rub a small dab of o-ring grease between your index finger and thumb. Then run the o-ring through your thumb and index finger, applying an even coat of grease. You will notice scum and pieces of grit and salt previously missed by the cloth will come off. Keep a towel nearby to wipe off this grit and reapply a small amount of clean grease to your fingers Run the o-ring through your fingers one more time. The grease will not only remove grit and scum it will condition and keep the o-ring from drying and cracking.
Don't overdo it with the o-ring grease. Too much grease can disrupt your seal and cause a flood. It's also important to note that some o-rings require a specific type of o-ring grease. Be sure to follow all manufacturers' recommendations before application of any grease. If the improper grease is used an o-ring can bloat and your housing may not seal properly. Some housings, such as Gates, recommend you not even use grease.
Clean your o-ring grooves. Take a q-tip and wet one end in your mouth. By wetting it, you will keep any filaments from the cotton head from falling off and ruining your seal. It will also allow the q-tip to conform to the shape of the o-ring groove. Then run the q-tip around the groove. This will pick up any grit that may have gathered there.
Once you've fully prepped your system and are ready to go, dunk it under water without you camera inside. Look for bubbles and be aware of you moisture alarm. A majority of the time, you'll have done your job correctly and won't have a flood, but if you do, at least your camera won't be destroyed.
For a list of items to take on your trip, to maintain your housing, please refer to my article, The Video System Check List.
Your monitor and lights each have a port that passes video signals and electrical currents from a battery or camera. If the connection for these currents is disrupted, your video feed will not work consistently or your lights will flicker or not come on. This is especially true with HID lights which need a consistent flow of electricity to work. The main obstruction to this electrical current is salt water oxidizing the bulkhead connectors and bulkhead ports. You can easily see this oxidation on the male pins of your monitor and light cables as a green patina or film. To remove this patina, simply fold a piece of fine grit sand paper to fit between the pins and gently rub until the connections are shiny. This should take very little effort or time.
To clean the female port of your housing bulk head, use a metal pipe cleaner. Get it into each hole and scrub until the invading crust is removed. Then blast air into the holes to ensure all is clear. I've fixed many "broken" lights and monitors this way.
Never travel with your camera inside its housing. When mounted on the housing tray, a camera, if jostled, can stress the tray's mounting screw and break. If this happens, you can have a moving camera rattling loose inside your housing. This will not only damage your tray but also your camera and the housing. Get yourself a good travel case, I like Pelican or Lowepro. These cases will protect your investment for as long as you have it. They're indispensable. The Pelican case, though a little heavier, is hard plastic and bullet proof. To shave off a few pounds, try a soft case by Lowepro. When choosing a case, buy one that is large enough for your system to grow into. A case too tightly packed can result in scratched and crunched gear.
Also, most planes are pressurized. A housing or battery pod sealed at sea level, can require super-human strength to open again once pressurized in the hull of a plane. To avoid this, travel with your housing slightly opened to release pressure.
When storing your housing, remove your ports and the back plate. Keeping a housing sealed will flatten your o-rings. Make sure your o-rings are greased so they don't dry out and crack. Also, and this is important, periodically charge all of your batteries. If you know you won't be diving for a long time, make sure to charge and discharge your light batteries at least once a month. If not charged for long periods of time, the chemistry in these batteries will no longer hold a charge. Since these batteries sell for $150-200, this is can be an expensive mistake.