Buoyancy disorder is a frustrating, multifactorial problem in fancy goldfish with no consistently effective therapies. For negative buoyancy, exogenous flotation can be provided by attaching flotation media to an implant (e.g., suture loop) or external framework. Implants may fail within days-weeks due to tension-induced pull-through. Two negatively-buoyant fancy goldfish were treated with a novel technique utilizing red rubber catheters implanted through the epaxial musculature as buoyancy loops. Catheter tips were cut at pointed angles and size 1 nylon suture (3/8 reverse-cutting) was passed retrograde through the lumens until the catheter tips abutted the needle base. With fish anesthetized, bites through the epaxial musculature were positioned halfway between the the dorsal fin base and the lateral line, or as deep into the muscle as otherwise able. The catheters were forced through the needle tracts by grasping the catheter and suture strand together using a needle holder to "push" from the entrance side while simultaneously "pulling" on the suture from the exit side. Catheter interactions with scales and/or epaxial skeleton complicated passage. Catheters were cut to size and the luminal suture was knotted to close each loop, leaving enough exposed suture for bobber attachment. Fish 1 received two loops (cranial/caudal); fish 2 received one cranial loop. The expanded surface area provided by the catheter is postulated to reduce tension-based cutting forces on the tissue, permitting much longer indwelling durations--a caudal loop in fish 1 remained for 9+ months. Post-op analgesia is required with this technique, as well as at-home wound management.