At some point in this hobby each of us will encounter some form of leak event. It is definitely one of the most stressful things that can happen. A leak can cause water stain to floors, and at worst case result in a catastrophic flood.  So the best thing to do is prepare for these emergencies.  Better yet, design it into your system to minimize flood damage and make a list of actions to follow in case of an emergency.  Most people will be quite frantic once they determine it is happening to them and will not be thinking things out logically. Prepare for this catastrophic event before it happens and hopefully, you will not need to implement it.

For those who are not in the engineering community there is a common practice called Failure Modes & Effects Analysis, or FMEA.  This article is just a simplification of this thought process.

Per the American Society of Quality, FMEA is defined as the following:

“Begun in the 1940s by the U.S. military, failure modes and effects analysis (FMEA) is a step-by-step approach for identifying all possible failures in a design, a manufacturing or assembly process, or a product or service. “

Design in Prevention

In this case, for leaks, here are some ideas to minimize failures and its effects.

• Purchase a quality tank (personally inspect the silicone seals and how well they are applied)
• Purchase a quality stand (personally I would stay away from those made with pressboard since they can absorb water, expand and structurally weaken resulting in a collapse)
• Ensure stand and tank are level.
• Plumb the system with true-union ball valves to allow isolating the tank from the sump and for quick disassembly and removal of the leaky tank.
• Waterproof the floor the tank will be placed on
• Add a drip basin or drain to catch or divert any spillage.
• Install leak detectors around the base of the tank and stand

Preventive Maintenance

• Inspection is the simplest form of prevention. Regularly examine and feel all your plumbing for salt creep and moisture.  If you see any you already have a leaky system.
• Regularly check and re-tighten all bulkheads. Rubber gaskets and O-rings will dry and shrink over time causing the nut to little loosen and not seal.
• Be careful scraping the glass near the seams. Inspect and see if the silicone sealant is peeling away.

Useful Items

• • Flex Seal tape
  • Teflon Tape (if using NPT/NPTF PVC fittings)
  • 100% Silicone Sealant (Aquarium Safe -No mold/mildew additives)
  • Thin Cyanoacrylate Glue and Baking Soda – Used to seal small active leaks if you can access it on the outside. The baking soda acts as a hardener.
  • Cyanoacrylate Gel for gluing under water
  • Temporary Holding System: Large container with extra heater, light and circulation pump (Clean Brute Trash Cans on wheels, or Rubbermaid stock tanks)
  • PVC cleaner, primer, and cement
  • Extra hose clamps
  • Matching sized PVC Compression couplings
  • Wet Dry Vacuum
  • Extra premixed saltwater
  • 5 gallon buckets
  • Extra water pump and long hose

Scenarios

If a leaky tank is encountered there are a couple of scenarios that can follow. Two will require some form of emptying the entire system and placing the livestock in a temporary holding system.  This is a lot of work in a short period of time but it is best to address it ASAP.

• Buying whole new tank to replace it on the same stand
  • If the stand is in good condition and will be reused removing everything to swap the tank out is the most straightforward.
• Buying a whole new tank and stand and transferring everything over.
  • Choose this only if the leak is very slow and not catastrophically imminent.
  • This option can eliminate the need for having a temporary holding system and lower the stress to the livestock.
• Repairing the Tank
  • Unfortunately It will all depend on quick identification of where the leak is. If it is high on the corner bead it would be simple enough to just drain the tank to expose the leaky area and attempt to re-seal and cure. If the leak is on the bottom edge the only true repair is to empty the entire system, clean, dry, strip all old silicone and re-silicone all edges. A full tank re-seal will take a few days of work and curing time.

Plan of Action

Whatever path you choose, it is best to outline all the steps you need prior to reacting.  It is a good exercise to think about it and document it for reference when time comes so you don’t miss anything during a chaotic period.

• Are replacement tanks / stands in stock locally?
• If you need help, who can you call and their availability?
• Larger tanks will need a lot of hands and / or mobility equipment (i.e. appliance dolly)
• If you are moving the system to a new location what is the travel path to the destination? Do you have enough room to fit it?
• List in sequence all actions needed to perform the tank swap (Example below)
  1. Check local availability, and buy new tank/stand
  2. Arrange time with friend to come help
  3. Purchase all things needed to install new system
  4. Level stand and plumb the new tank
  5. Shut off leaky system and move sump and nonessential equipment. (Leave heater and circulation pump for now)
  6. Drain through filter sock as much of the existing tank water into the new tank
  7. Transfer the rocks and corals for a quick aquascape
  8. Drain water as low as possible to catch and transfer all fish
  9. Top off new system with fresh saltwater
  10. Rinse out sand with remaining tank water to slowly adding back to the new system. If the sand is too dirty you’ll have to wash in freshwater and add over time
  11. Expect some form of cycling to occur when everything is disturbed or adding new rocks or sand