7. To prime the siphon in the U-Tube, the air must be removed from the inside of the tube. This will be achieved by
sucking on the airline tubing until the U-Tube is full of water. One good pull of air should achieve this. Once
primed, the water will automatically reach an even level on both sides. The airline tubing should be removed
once the U-Tube primed.
8. Water will now begin to siphon from your aquarium to your external filter. Plug in your return pump to avoid
over-draining your aquarium and keep a constant prime inside the U-tube. The flow rate of your return pump
should closely match that of the overflow box rating to avoid draining issues.
Return flow should never exceed
the rated flow rate for the overflow box.
At this point, it may be necessary to add water to your system. Keep an
eye on the U-Tube and aquarium to ensure that the siphon is maintained and water overflows freely and easily.
9. Inspect for any air pockets or bubbles that may accumulate at the top of the U-Tube. During normal operation,
no air should accumulate at the top of the U-Tube as proper water flow will force any bubbles all the way
through the U-Tube. If air accumulates in the U-Tube, check to make sure the overflow box is completely parallel
to your aquarium and your return pump has sufficient water flow.
10. Proper attention must be given to the external filter. Ensure that the return pump is completely submerged and
that your filter is not accumulating water past its maximum water level. It may be necessary to add or remove
water. Continue to monitor your aquarium, overflow box and external filter for a few minutes to ensure that
they are working properly; inspect for leaks and ensure water continues to drain into your external filter.
11. The Marine Depot Overflow Box is designed to automatically restart after a power outage, or if the return pump
is turned off then turned back on. The U-Tube should remain full of water when the return pump is off. You can
test for functionality by simple turning off your return pump for 1-2 minutes, once the return pump is switched
back on, the siphon should automatically continue.
As with any overflow system, it is critical that your water level is constantly maintained by means of a top off system
or by regular manual top offs.
