Make sure the pressure locking thumbscrew is correctly aligned when sealing the underwater housing (i.e. NOT cross threaded). There should be no gap between the waterproof door and housing body.

Pushing the up (display) button on the side of the camera will turn the display off and on for power-saving purposes.  Make sure the button was not pressed by accident.

The ReefMaster RM-4K camera is compatible with Micro SDXC Class UHS Class 3 (U3) or Video Class 30 (V30) memory cards. UHS Class 1 (U1) or Video Class 10 (V10) cards do not have a fast enough read/write speed and cause “card error” message or camera lock-up.

We recommend memory card size of 128GB or 256GB made by a reputable brand, like SanDisk, Delkin, Samsung, Panasonic, Kingston, PNY, Transcend or Lexar. We will post updates regarding the use of newer, high memory 512GB+ cards after more tests are completed.

* In the event of a camera lock-up. Push the Power and Shutter buttons at the same time to force-off the camera.

If ReefMaster app shows “Camera Not Connected” message but iPhone Wi-Fi settings shows camera is connected, the Local Network have not been allowed.  To allow Local Network permission, go to iPhone Settings, scroll down to ReefMaster app and allow Local Network.

Search app store for “ReefMaster”. The Instruction Manual says to search for “SeaLife ReefMaster”, which is not correct and will be updated.

On October 27, 2023, SeaLife released ReefMaster app update version V1.4.7 to Google Play app store.  The update fixes some minor bugs associated with Android 13 and 15 operating systems.  Please update your ReefMaster Android app via Google Play app store.  Report any bugs or issues to quality@sealife-cameras.com.

It’s a known fact that many sunscreens contain chemicals harmful to reefs and marine life. These same chemicals are also damaging to some plastics, including polycarbonate commonly used to manufacture underwater camera housings and diving equipment. Test results confirm that spray-on sunscreens are particularly aggressive causing a chemical reaction that can make the material become brittle and crack.

SeaLife UW cameras/lights and some accessories are manufactured from a high-quality grade of polycarbonate. Polycarbonate is used in many products where high impact resistance and/or optical transparency is important. Such products include sports safety equipment, medical devices, automotive parts and electronic device housings, to name only a few. Despite polycarbonate’s impressive engineering characteristics and expansive presence in modern life, it is unfortunately susceptible to damage from some sunscreens.

We highly recommend using sunscreens that are advertised as safe for oceans and reefs. If you use a spray-on sunscreen, never apply it around your diving equipment or UW cameras/lights. Always wash your hands after applying sunscreen to avoid contaminating plastic material when handling it. Soak and rinse your cameras, lenses and lights for 20 minutes and allow to completely dry before storage.

Do not connect any accessory to the camera’s ¼-20 tripod mount where the screw length exceeds 0.3” (7.5mm). Using a ¼-20 screw that is too long will bottom out in the tripod hole and create a high degree of stress to the camera housing material that may result in cracks and consequential flooding.

Also, never apply thread-locking compound or any chemicals to the tripod mount area. These compounds may cause chemical reaction that permanently damages the camera housing material and consequential flooding.

In Playback mode thumbnail view[A], you can delete the selected photo or video by pushing and holding shutter button. The camera will display “Delete File” – “Single File” or “ALL Files”[B]. Select the desired option using the up or down buttons. The camera will display “No” or “Yes”[C]. Select Yes to delete or select No if you do not want to delete the file. Push Power/Mode button at any time to cancel and return to thumbnail view. You may also format the camera to delete all files.

There are no known issues that cause a lock-up except for using a noncompatible memory card.

The ReefMaster RM-4K camera is compatible with Micro SDXC Class UHS Class 3 (U3) or Video Class 30