The business is to be an online retailer of spearfishing and freediving equipment. The target audience is young athletic males - think 20's and early 30's, lots of energy and into a hardcore and dangerous sport. There are a two options that could work for branding:
1) A 'hardcore' logo that highlights the element of hunting fish underwater. A tribal design might be good for this
2) A more earthy logo to reflect the relationship between the diver and the ocean environment, the peacefulness of being underwater, surrounded by the vastness of the ocean
Watch these videos to understand what the sport is about - the logo will need to capture the 'spirit' and feeling of the type of activities done in these videos
The logo will need to be used on the website, and on various types of product: stickers to put on spearguns, raised embossing on rubber and plastic products, and on the front and back of wetsuits, so it should be simple enough to stand out on these products.
A lot of marketing will be done from filming users using the equipment underwater, so the logo will need to be instantly recognisable even in underwater pictures, however it still needs to look great on a website. It would be acceptable to have a color version for the website and just use black and white version on product.
The website is allthingsspearfishing.com, so maybe incorporate the .com into the design. 'all things' can be small if needed, but 'spearfishing' should remain large font since that's the essence of what the brand will sell. To see the types of product check google images using these searches: 'speargun', 'Freediving fins', 'Spearfishing wetsuit'