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Marker Float Deployment for Benthic Chambers

The AquaBob™ Marker Float is used to mark the location of the benthic chamber under water.  The marker float is a highly buoyant, durable HDPE buoy with a reflective red stripe and high-visibility yellow stripe.  These floating marker buoys save time in quickly locating your benthic chambers when you have multiple chambers deployed over a large area.  The AquaBob™ marker float can be used to mark the location of a wide range of underwater objects.  This marker float is not a navigational buoy.

How to Use the AquaBob™ Marker Float

The bottom of the AquaBob Marker Float features a closed steel eye-hook.  One end of the requisite length of nylon line is tied to the eye-hook, and the other end is secured to the included carabiner.  The carabiner is always anchored to the ControlPak-S™, never to a screw-anchor, anchor lines or any part of the benthic chamber.  (See Fig. A below)  The reason for this is that if the marker float were to ever get entangled with a surface object, the nylon line attached to it would likely be pulled up with some force.  If the line were attached to the benthic chamber, the chamber might be pulled free from the sediment or it may topple over.  But if the line were attached to the ControlPak-S�, it would simply snap, since the ControlPak-S� weighs over 23 lbs (10.4kg) and the nylon line is unable to lift that heavy weight. 

Fig. A.  Profile view of the Aquos™ BC-8 Benthic Chamber, anchored to the sediment using Screw-type anchors, and connected to the ControlPak-S™ power source.  The AquaBob Marker Float is connected to the ControlPak-S™ via a carabiner (included with the AquaBob™).

For the same reason, we recommend that you do not substitute the line we provide with  a heavier gauge line.  If the marker float is tied to a heavier line and the float gets entangled with a surface object, the line will not snap, and might serve to drag the ControlPak-S™ to a distant location deeper underwater, where it may be lost.

When a grappling anchor is being deployed with the Aquos™ BC-8 Benthic Chamber, the marker float carabiner should be secured to the metal loop at the bottom of the grappling anchor.  (See Fig. B)  If the benthic chamber does break free from the sediment and get dragged along the bottom to another location, the marker float will indicate where the grappling anchor has managed to dig itself into the sediment again, making it easy to locate the benthic chamber after such an event.

Fig. B.  Profile view of the Aquos™ BC-8 Benthic Chamber, anchored to the sediment using Screw-type anchors and a grappling anchor, and connected to the ControlPak-S™ power source.  The AquaBob™ Marker Float is connected to the grappling anchor via a carabiner (included with the AquaBob™).

How long should the marker float's nylon line be?

The length of the nylon line depends on two factors:

• The depth at which the benthic chamber is deployed
• The maximum height of water during high tide, where applicable

A good rule of thumb would be to add 4-5 feet to the maximum depth (or high water mark during high tide) that the benthic chamber is being deployed at.  Tie one end of the line to the carabiner and the other end to the eye-hook of the AquaBob™ Marker Float. 

How to secure the carabiner to the ControlPak-S™

Tie one end of the required length of nylon line that is supplied with the AquaBob™ Marker Float to the eye-hook at the bottom of the float, and the other end to the locking carabiner.  We recommend a strong, slip-proof knot for tying off the nylon line and one such knot is the Uni knot.

The carabiner is secured to a strong pin that is located on the front of the ControlPak case, near the handle.  Once the carabiner is secured around this pin, the carabiner is locked to prevent its accidental opening.  See image above.