If you can read all five items on this key, you didn't buy this sweatshirt — you earned it. FIG. 1 is a clean mid-century cutaway of a working saltwater reef tank system: display tank up top, sump and skimmer below, every part called out in a numbered legend. And item 5? Any reefer already knows why the alk swing is not shown.
Printed on a Gildan 18000 unisex crewneck — a heavyweight, medium-soft fleece with a classic roomy fit, ribbed cuffs and collar that keep their shape. The blueprint-white linework and deep reef-blue display tank read crisp and bold on dark fabric, with signal-amber callout numbers for that owner's-manual detail. Available in 8 colors, from true black through navy, forest green, and heathered greys.
The one you reach for on a water-change morning, or wear to the frag swap when it's finally cold enough. A build-completion marker, a tank-anniversary gift, or a quiet flag for a fellow reef keeper.
Made to order and printed just for you, so it's produced fresh (typically 3–7 business days) before it ships. Shipping times vary by location. Care: machine wash cold inside out, tumble dry low, do not iron directly on the print.
Drafted like the manual. Worn like a badge.
