Building My 50,000 Gallon Monster Mega Tank


Gold Tier VIP
MFK Member
Sep 13, 2005
Remember you are only restricted by the size of your dream.
and I dream MEGA


I built my mega and mini mega tanks in the 1994 to 1997 period.

My mega tank: I built the tank as an addition to the home and then joined it by putting doors through the basement and upstairs through the bedroom. You can see the excavator removing the soil on the first week of construction. You can see the doors cut through my walls in the 3rd picture.

The lower section has my tank and the upper section I keep my tropical birds. I had to do it on a budget so it is not fancy like a public Aquarium. It took me 9 years to save the money and 1 year from start to water in the tank. It is now in its 11th year with water. In the picture below you can see Mike Mosely and my brother Bob installing the base plates for the angle iron, which were cemented (lower 4 feet) and formed the frame for the glass to be inserted. I was restricted in it being a beautiful landscaped tank because of my injuries I am physically very limited and could not do much in its construction since I am paralyzed from the upper chest down.

I honestly only expected it to hold water for about 10 years, so I am doing better than expected. My large tank is L shaped. The long part of the L is 36 feet, the short part of the L is 27 feet. The front to back of the long part of the L is 18 feet, the front to back of the short part of the L is 15 feet. The tank water is 9 feet deep. Notice in the picture above that I built a 4 foot high wall dividing the tank somewhat. The wall serves several purposes: 1. It and the L shape reduce aggression by stopping eye contact at times among predatory fish. 2. It helps brace the tank 3. It allows me to drain one side or the ther and just move fish into the side with the water in case I need to make repairs. The Aquarium holds a little over 50,000 US gallons. The floor area of the aquarium is 800 square feet. I only have glass on the top 5 feet of the tank and have a floor at that level so I can feed the fish etc.. from my wheelchair. In this tank I keep many small cichlids, barbs and characins. A viewing glass area was put into the the ceiling of the aquarium to admire the fish from above. As well 11 skylights were put into the roof of the bird room above so that beams of sunlight could come into the tank at different angles during the day. As well the glass panel was hinged allowing easy physical access to the aquarium to replace bulbs etc. via a rubber dinghy.

In the picture on the below you can see Dominic Zanelli getting into the dinghy. TWO problems arose from this 1. The glass panel 6x2 feet was too difficult too keep clean. 2. Some of the fish bit the dinghy causing it too leak. Dominic got his 6'3" 225 lb frame out of the tank fast !!!! SOLUTION: 1. remove the glass panel access door with a solid one 2. Buy a British military dinghy made of material the fish have not punctured in the last 10 years (So far).

I put in two small windows above the water line to get some natural light. One facing south the other north to get some natural light at those times. Jan Klazynski can be seen siliconing the window to the concrete. The concrete I had sand blasted to remove imperfections and get a very smooth finish, then epoxyed and two coats of a siliconed water proof paint. PROBLEM: The second coat never adhered to the first properly causing the second coat to peel off over the years. Unsightly but the tank does not leak (YET!).

My daughter Nikki and her husband Richard are putting the Lava Rock into the tank.. The lava Rock would 1. create hiding spots for the many small fish (under 12") in the tank to avoid the serious predators and give their babies a place of refuge. 2. Create a natural filter for the aquarium.

This was a good time to put the large pieces of driftwood in as well. Also the plumbing was installed Sean Wilson and Duncan Worthington. I had placed 4 swimming pool drains into the bottom of the aquarium and 1 swimming pool skimmer at the 9 foot water level. The driftwood had been soaked in my outside ponds for 3 to 5 years in preparation.

Next the glass had to be put in place by John Petersen his son and my brother Bob. The panels are 5x3 and 1" thick. GE1200 silicone was used.

My friend Dominic is installing 6 sodium lights and 12 double fluorescent fixtures. I also installed 10 sets of halogen 500 watt fixtures but removed them over the first year because of short bulb life. Notice the 2nd and 3rd pictures below. I have filled one side of the Aquarium to make sure there is no leakage at the 4 foot safety wall. IT WORKS !

The pictures below show the filling up process. It takes 7 days to fill. The Aquarium was filled and drained over 3 month period 5 times to insure any toxins were flushed out.

The green tinge to the water disappeared over the first year.

At this time I am having problems with my steel above the water line rusting. I built 10 access doors to feed the fish etc. and they are rusting also. I had problems with the floor above the tank after the first year because the floor materials absorbed water and weakened. I then had to replace the floor. I heat my tank with a house oil fired hot water tank. I have used 2 swimming pool heaters before this. But I had many problems 1. the first one ran great for 5 years but it had been installed improperly by the seller and caused a fire. The second one was far too big and it started leaking in the boiler after 1 and a half years. I use a 600 lb sand filter on the mega tank, the natural lava rock filtration, I don't over feed and I do about 10,000 gallon water changes every week.

Mae West once said "Too much of a good thing is wonderful"

Please note that none of this article or pictures can be reproduced or used in any article or story without my verbal and written permission.


Feeder Fish
MFK Member
Jul 12, 2005
I USED to think I had a problem but now I know who has a problem and it's not me :ROFL:

I bow to your love of fish. I will show this to my wife and she will be scared that I want one.... I do want one.


Feeder Fish
MFK Member
Jun 22, 2005
Milwaukee, Wisconsin
:drool: :WHOA: :drool: :WHOA: :drool: :WHOA: :drool:

I am on my knees.....I bow to thee oh fish am utterly amazed!

Jen ;)
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Feeder Fish
MFK Member
May 27, 2005
:WHOA: I cannot believe my eyes... That is awesome man beyond impressive.. I bet all the members would love to see more pictures of the fish inside the tanks..