Alexander Kornek Instructor Instuctor OC-Open Water Nitrox Diver OC-Advanced-Nitrox-Open-Water-Diver OC-Nitrox-Diver OC-Normoxic Trimix-Diver OC-Decompression-Diver OC-Recreational Trimix-Diver OC-DPV-Diver OC-Drysuit-Diver OC-Rescue-Diver