I let everything run for a week or two to see if I'd have any problems. To be honest, I did. 3 of the 1
1/2" bulkheads began to leak, and I had alot of bubbles being returned to the tank from both pumps. I
traced the leaking bulkheads back to my installation procedure. I had read many opinions on the best way
to install bulkheads. One common suggestion was to apply silicone sealant to the rubber gaskets during
installation. So I did. This proved to be a fatal error on my part. In my opinion adding silicone
sealant to the gaskets will almost guarantee that they DO leak, not help prevent it.
My opinion is based on the following:
-
The silicone will make the gaskets slippery during installation. This will cause the gaskets to tend
to slip out of place when being compressed between the two surfaces.
-
If the bulkheads are moved/retightened after the silicone has had a chance to set, then the silicone
will "ball up" creating voids between the bulkhead and wall. These voids will eventually leak.
So I drained the tank below the bulkheads, and replaced all of the gaskets. This process was made much
worse by the fact that I had to try to save/store over 1000 gallons of saltwater. Lesson Learned.
The bubbles being returned to the tank turned out to be a combination of problems. The open loop pump had
a small leak at the inlet, which allowed air to be sucked in when the pump was powered up. I did not find
this problem until I shut the pumps down for about an hour to look for leaks. The bubble problem on the
closed loop pump turned out to be cavitation. To cure the problem, I simply cut back the flow (about 5
degrees) using the ball valves on the manifold.
After another 3 week test period, I began adding my live rock, live sand, and a few damsels to get my
cycle kicked off. During the cycle period, I constructed a 12" wide splash guard from 1/4" acrylic which
surrounds the perimeter of the tank. The prevents the waves and occasion splash from a shark from making
a mess on the side of the tank. It also helps with evaporation. I also added a heavy duty 3/16" thick
plastic net to the top of the tank which is held in place with a series of hooks and cords. The purpose
of the net is to prevent the sharks from jumping out of the tank.
For lighting, I simply purchased 4 48" double bulb fluorescent lighting fixtures, with cold start
ballast's from Home Depot. I purchased 8 48" aquarium bulbs, 4 actinic and 4 daylight. The lights are
suspended over the tank on chains, and on a timer for 6 hours.
I took several measures to control the excess humidity generated by the tank. Green board was used on all
non-concrete walls in the tank room. I sealed all of the concrete walls with several coats of concrete
sealant. Next I lined the entire room with heavy gauge plastic lining. I added air exchange fans to keep
a constant supply of fresh air in the tank room. A large exhaust fan is in the works, which will draw air
from above the tank, and vent to the exterior of the house, and I have a large dehumidifier on order.
The rest is history. As of today 03/29/2003, the tank itself has held water without any leaks, signs of
stress or warpage for 9 months. The entire system has been trouble free since the initial bulkhead
incident 6 months ago.
The purpose of this article is to give an overview of what I did, and how I did it. I would like to
point out that what has worked for me may not work for you. I in no way make any guarantees or promises
on the design/plans listed above. In other words, build this tank at your own risk :) If there is any
additional information anyone would like, please feel free to either post your questions/comments here,
or contact me directly at nacnacmxr2@aol.com. □