This is a collection of direct links to our knowledge base of educational content that appears on the Dive Gear Express website mostly in the form of brief blocks of diving related information that are distinct from our product descriptions and administration content. This knowledge is primarily focused on experienced sport and technical SCUBA divers. It may not be useful to those just now learning to dive, and in some cases might even contradict instructor recommendations to entry level divers.

Our popular Tek-Tips are product independent information attached to the bottom of various category and product pages. There is some product related information, such as our opinions on specific product selection or usage, that we list in a separate Product-Tips category. We have a few longer discussions that we list under the Articles category.

The Dive Gear Express YouTube Channel contains a library of our in-house produced information videos. Each video is focused on important facts for a single topic, omitting extraneous promotional content and excessive detail. The videos are fast paced to keep them compact, about one to three minutes in length with pause and rewind controls always available during viewing.


  1. Compressor Lubricants and Diver Safety
  2. Compressor Lubrication for SCUBA
  3. Nitrox and Compressor Lubrication
  4. "OMG" Is your QR insurance paid up?
  5. Marine Grade Stainless Markings Must Be Annealed
  6. Your Hands and Feet Can Be Larger When Diving
  7. Is My HP Tank 3/4 NPS or 7/8 UNF Neck Threads?
  8. Seriously, Do Not Pee On That...
  9. The 411 on Dive Instrument Consoles vs Wrist Mounts
  10. Using a Signal Mirror for Rescue
  11. Handling Emergency Oxygen Kits
  12. How do the grades of compressed oxygen differ?
  13. Units of Pressure in Diving
  14. Servicing SCUBA Hoses
  15. Damaged 300 bar DIN valve outlets
  16. Can Nitrox or Trimix be run through a breathing air compressor?
  17. About Gas Time Remaining (GTR) Calculations
  18. Aluminum vs. Stainless Hardware
  19. Single-Tank-Adapters or Assembly Screws Are Often Counterproductive
  20. A unified and robust solution for dive logging software
  21. Sunscreen and Dive Computers
  22. How do you stay warm in a neoprene wetsuit? Take it off.
  23. Do I really need that big NITROX wrap decal on my tank?
  24. Advice for Flying with SCUBA tanks
  25. How to use a twist-on handheld dive light or strobe
  26. Diving and Blue Pills
  27. Divemasters Should Ask 'Is Your Oxygen ON?'
  28. The R-22 and R-17 type oxygen sensors in diving
  29. Lubrication and SCUBA Valve Installation
  30. Using PTFE (aka Teflon) Thread Seal Tape with Oxygen, Nitrox and Trimix
  31. Metric vs Imperial SCUBA Cylinder Sizes
  32. Rechargeable Battery Chemistry for Dive Lights - Lithium Ion
  33. ADVISORY: Oxidane and Diving
  34. 'The Skinny' on Snorkels and SCUBA Diving
  35. Helium Grades for Breathing Gases in Diving
  36. SCUBA Cylinder Neck Threads and Pressures in North America
  37. When is Enough... Enough?
  38. Soft Plate Systems and Metal Backplates
  39. Where do I get replacement batteries?
  40. Environmentally Sealing SCUBA Regulators
  41. How Deep is DEEP and How Cold is COLD?
  42. The Original Sidewinding Style Cave Reel
  43. Line Markers
  44. The History Behind the K-inflator and Drift-Pin vs. Schrader Inflators
  45. B├╝hlmann versus VPM Decompression Schedules
  46. Open Water Students and Modern Equipment Configurations
  47. High Pressure Swivel Spindles aka 'Air Spools'
  48. BC, HP, IP, LP and MP
  49. Helium Penalty? What Penalty?
  50. White, Orange or Chartreuse; which is better?
  51. Quick-Disconnect Compatibility and Lack Thereof
  52. Calibrating Oxygen Analyzers for Diving
  53. Dust caps with DIN-to-Yoke adapters are not best practice
  54. Rigging the SPG on Stage and Sidemount Bottles
  55. Many Mass-Market Cleaning Products Can Damage Your Dive Gear
  56. What is the knob and lever on my second stage?
  57. Make Your Own Custom Length LP or BC Hose
  58. A Battery Warning Means You Are Diving On Borrowed Time!
  59. Backup Second Stages
  60. Buddies and BC Integrated Regs
  61. Choosing the Best Inflation Hose Length
  62. Choosing the Best Primary SPG Hose Length
  63. Cleaning Low Current Electrical Contacts
  64. Compass Balance Zones
  65. Just Say No to Deep Air
  66. Do You Know Your Right From Your Left?
  67. DPV Battery Technology Tradeoffs
  68. Evolution of Manifolds and Bands
  69. Full Face Masks and Recreational Scuba
  70. Gearing Up With a Long Hose
  71. Get the Lead Out!
  72. History of the Finger Spool
  73. How Long is Your Hose?
  74. How Much and Where to Use Lubricant
  75. How to Overhaul a Power Inflator
  76. Independent Twins Are Not Doubles
  77. Regulator Intermediate Pressure (IP)
  78. Tang? Pommel? Drop Point? Swage? Spine?
  79. Leaking Mask? Loosen The Strap!
  80. Candela vs Lumen
  81. Mixing Brands or Ages of Oxygen Sensors
  82. Dispelling the Myth of the Simple Oxygen Flush Test
  83. Burst Disks in SCUBA Valves Are Not What You Think
  84. Rebreather Training
  85. Self-Operated vs Pilot-Operated
  86. "Sidemount diving makes technical diving easy" - Jeff Loflin
  87. Sidemount Configurations
  88. Who's Your Buddy... Han?
  89. SPG Floods
  90. Time to Fly? Maybe Not.
  91. What Color is Your Parachute Bag?
  92. What Happened to Low-Pressure (LP) Cylinders?
  93. What if you donate your primary?
  94. What Size Fins Do I Need?
  95. Choosing the Best Regulator Hose Length
  96. Optical Coating Masks Are Not "Cool"
  97. Plan Your Dive - Dive Your Plan
  98. Looping Hoses Under Hose Retainers
  99. Does the Vindicator knob make sense for experienced divers?
  100. Valves for Sidemount
  101. Single Tank Mounting with Backplates
  102. Bad BCD Maintenance = Provoking Instead of Preventing
  103. Types of Back Inflation BC Systems
  104. The Origin of Hogarthian Configuration
  105. Interchangeability of Backplates and Wings
  106. Which Wing Do I Need?
  107. Helmets Have Their Place In Diving
  108. How to Glue On Your Glue-On Pocket
  109. Why Black Dive Masks Are Better
  110. Beware of Fin Hyperbole
  111. Ordering Vision Correcting Lenses for Dive Masks
  112. Mask Defoggers Explained
  113. Give Tank Boots the Boot, Decals Too!
  114. Installing Valves in SCUBA Cylinders
  115. What Happened to My Gas?
  116. Perfect Positioning of Decals
  117. Common Uses for Stainless Steel Snaps
  118. Canister vs Handheld Lights
  119. The Best Things in Life are FREE
  120. Oxygen Sensor Life in Rebreathers
  121. Piston vs Diaphragm... Does it really matter?
  122. Upstream vs Downstream
  123. Long Hose Regulator Configuration for Single Tank Diving
  124. Do You Sidemount Up or Down?
  125. Choosing Stage/Deco Regulators
  126. Bailout/Deco Regulators
  127. Inspect Your Regulator Mouthpiece
  128. Hose Protectors Don't
  129. The Oxygen Shutoff Is a Mixed-Bag
  130. Take Only What You Need, No More and No Less
  131. Tiny Bubbles?
  132. Mr. Cleaning Your Dive Slate and Wetnotes
  133. BCD Bladder Repairs
  134. Blame Normalization of Deviance, Not "Complacency"
  135. ZHL, VPM, RGBM, DSAT, DCIEM, DCAP ... Does It Really Matter?
  136. Manifold Crossbar Isolator Valves May Not Improve Safety
  137. Sanitizers, Disinfectants, Antiseptics and Your Rebreather & Regulators
  138. Finger Spools Are Not Reels
  139. SCUBA Regulators and Hoses Nomenclature
  140. Fixed Port vs Swivel Turret
  141. Lumens, Lux, Burn Time and Kelvin - Caveat Emptor
  142. Open Circuit Etiquette with Closed Circuit Divers
  143. StainLESS does not mean StainPROOF
  144. Form vs. Function in Dive Masks
  145. About the U.S. Diver Down Flag
  146. Using the metal grommets......
  147. Will back inflation float an unconscious diver face up?
  148. Stage Straps
  149. You Can't Get Everything On-Line
  150. What about "black face" instruments?
  151. OOPS.... NOT!
  152. Hogarthian Regulator Configuration for Doubles
  153. Learning From Analysis of Rebreather Deaths
  154. Gradient Factors
  155. Sidemount Diving Has Gone Mainstream
  156. What is the difference between "200 Bar" and "300 Bar" fittings?
  157. Threading a 3-Slot Quick-Release Belt Buckle
  158. Regulator Necklaces
  159. Selection, Care and Maintenance for Reels
  160. Nitrox? Heliox? Helitrox? Triox? Normoxic Trimix? Hypoxic Trimix? Heliair?
  161. Care and Feeding of Lithium Chemistry Rechargeable Batteries
  162. Are Rebreathers Safe?
  163. Uncoupling DIN Fittings From SCUBA Valves
  164. Inside Submersible Pressure Gauges
  165. Streamlined Open Water Regulator Configuration
  166. Sizing and Selecting O-Rings for SCUBA
  167. How to Choose Between Lift Bags and Marking Tubes
  168. A Gas Booster Reality Check


  1. Apeks XTX Series First Stage Differences
  2. Low-Pressure Breathing Gas Fittings on SCUBA Regulators and Hoses
  3. DGX No Longer Sells SAFT Lithium Batteries
  4. How are the DGX Premium O2 Valves different from DGX Premium Nitrox Ready Valves?
  5. Dive Rite XT Regulator Differences
  6. How to resurrect a completely dead Poseidon Smart Module
  7. Differences of Teric vs Perdix 2 Ti Dive Computers
  8. Regulators and Required-stop Accelerated Decompression
  9. Garmin Descent Mk2/Mk2i/Mk2s Model Differences
  10. Backplates and Your Height
  11. DGX Gears brand D6 and XTRA regulators
  12. Apeks XTX Series Second Stage Differences
  13. Differences of Petrel vs Perdix Dive Computers
  14. Characteristics of Line on Dive Reels and Finger Spools
  15. SCUBA Regulator DIN Connector O-ring Sizes
  16. R-22 Oxygen Sensors - 'D' type vs 'S' type
  17. CO2 Absorbent: 797 vs 812 vs 1025
  18. Why Choose SI TECH?
  19. Garmin Descent G Series vs Mk Series Differences
  20. Why Choose Apeks?
  21. Choosing Between the DGX Gears 1000-6 and 1000-8 Handheld Lights
  22. Drive Gas Options for the Booster
  23. Peregrine vs Perdix 2
  24. Alternative hose configuration for your Poseidon DSV/ADV/BOV
  25. Why we are ashamed to sell these...
  26. Differences Between DGX and Thermo Brand Valves
  27. Why Choose XR by Mares?
  28. SPG Depth Ratings
  29. Why Choose DIVESOFT?
  30. The NERD 2 from Shearwater Research
  31. Maintaining Poseidon Cable Connectors
  32. Basketball Shoes for Diving... Seriously?
  33. Recreational Nitrox Configuration of Shearwater Perdix
  34. Advice regarding travel with Sofnolime
  35. Replacing Air Cell Inflation Assembly Elbows
  36. Why Choose DGX Gears™ Brand Products?
  37. Why Choose Shearwater Research Dive Computers?
  38. Why dive Poseidon?
  39. Compare the DGX 300 - 600 - 800 lights
  40. Why Choose Analytical Industries?
  41. Aluminum Cylinders at Dive Gear Express
  42. Why Choose Dive Rite?
  43. Why Choose Omni-Swivel International Products?
  44. Steel Specialty Cylinders by Faber
  45. Dive Rite Air Cells Overview
  46. Steel High Pressure Cylinders by Faber
  47. Dive Rite Dual Armored Wing Options
  48. Dive Rite's Gusset Control System
  49. Why Choose Ocean Management Systems?
  50. TransPac, TransPlate, and Hydro Lite Sizing
  51. Light Mount Sizing Chart
  52. Nomad XT/LTZ/LT/LS Tank Mount Configuration Options
  53. Why Choose G-Dive?
  54. DGX Custom Regulators - Have It Your Way


  1. Z Factors for SCUBA
  2. Choosing Your First Rebreather
  3. How to Select a SCUBA Tank
  4. Calculating SCUBA Cylinder Capacity
  5. CCR FAQ - rEvo
  6. CCR FAQ - O2ptima
  7. SCUBA Valves
  8. How to Attach a Snap
  9. Oxygen Sensor Handling
  10. Assembling Double Cylinders
  11. What is a Rebreather?
  12. Suggestions for Selecting a Wing
  13. Sofnolime Absorbent Selection And Handling
  14. About Oxygen Disclaimers
  15. DGX Gears Harness Assembly Instructions
  16. O2ptima Scrubber Duration Test Results
  17. CCR FAQ - Poseidon Se7en+
  18. South East Florida Diving Logistics
  19. Lift Bags versus Marking Tubes
  20. Understanding Nitrox Ready and Oxygen Service