Any tail with a monofin that isn’t on the safe monofin list
Good / Safe Tails (Silicone tails)
* Please note; Silicone tails are NOT recommended as first time tails.
Silicone tails must contain a safe monofin and be made from skin safe silicone in order to be safe. The skin safe silicone used by top tailmakers is called Dragonskin Silicone.
Bad / Unsafe Tails (Silicone tails)
AVOID SILICONE CAULKINGS, these can be extremely toxic to you, others, and marine life. Even if the caulking doesn’t touch your skin directly, toxins from the caulk can leech out into the water with you and be absorbed through the skin. Caulk is not regulated or tested for skin use, it is made for bathroom sinks. Aquarium safe DOES NOT mean skin safe. Aquarium safe means in small amounts, it could be put on fish tanks and the fish won’t die.
Tails that contain monofins NOT on the list of Safe monofins (above) Should be AVOIDED