Supporting the Tank
Supporting the Tank
They say as a general rule of thumb that a glass reef aquarium with substrate and rocks filled with saltwater will weight around 10 lbs per gallon. At 225 gallons, that is a very loosely estimated 2250 lbs. I'm not sure if the rule of thumb works for large tanks cause having took six guys to bring that tank into the house, I know the tank weights a few hundred pounds on its own and I feel the estimated 2250 lbs is shy a few hundred pounds. Regardless, the general rule of thumb for residential floor loading is around 40 lbs per square feet. The tank foot print is 15 square feet, so quick math, I can safely support 600 lbs. Yikes! "¦
So, having heard the horror stories of large tankers busting seams and flooding their downstairs neighbours with saltwater destroying their house and killing all their livestock; I know I have to reinforce my floor. Once I build the tank, I won't be able to afford a divorce so I better spend a few bucks up front and make sure my floor stays put and the water stays in the tank. The location of the tank is non-negotiable; I want it exactly where I want it. Down to the basement"¦ where I of course find that my floor joists are running in parallel with the direction of the tank. !^#@&*. Remember my tank is 30" deep and floor joists are on center every 16". What are the odds that I would only be on one joist? I'm that lucky"¦ So let us divide the estimated weight of that tank into two representing each side of the stand. That puts 1125 lbs of weight on one 2x10 at about 1' from the steel support beam and another 1125 lbs of weight on the same 2x10 at about 7' from its nearest support. There is no way that one old piece of pine under all that weight is not going to deflect before I'm even done filling the tank with water.
The goal is to support the tank with a structure that is perfectly level in both dimensions and will not move during filling, or when I'm out for dinner with my wife, or in 6 months or in 3 years, or ever"¦
So, after considering all the problems associated with different possible solutions (existing finished room in basement, existing plumbing, existing wiring, existing ductwork, erecting post in my basement) I decided to go with the following:
1- Add six 2x10s as additional parallel joist to the existing floor structure. 3 for the back of the tank and 3 for the front of the tank. These will be fastened together with 3" deck screws and glued with construction adhesive to form 2 solid beams. Plus I get the 2x10 in the middle that is already there.
2- Add two steel jack posts exactly under the corners of one side on the tank that would otherwise be in middle of the floor joist span.
So now I have 2 corners exactly on 2 steel jack posts that sit on a poured concrete foundation and the other side of my tank sits on seven 2x10s that are about 1' from the steel beam which is itself supported by another existing jack post within maybe a foot. I figure seven 2x10s under half the tank weight wont deflect much for the 1' span to the main support. But I keep telling the wife it would have been safer to get the seven foot tank. I'll know for next time...
Problems: To get the 2x10s in, I have to 1-move the wiring, 2-move copper piping (main cold water), 3-temporarily remove main stack cold air return ductwork, 4-temporarily remove large hot air stack ductwork (in January)"¦
Pics for you guys...
Okay so this in my basement, right underneath the tank. The tank runs perpendicular to that wall. Those 2 ropes green and white dangling from the ceiling on the right side of the picture are right underneath two corners of the tank and where I will be putting two jack posts. The picture is of the back wall of my shop which will be somewhat converted to a fish room. The shelves are staying but will hold fish equipment rather than food and diapers...
Okay this one just shows job #1. Get that ductwork down cause it's in my way...
Ductwork down. Now that strapping and those crosses have to come out.
Getting there... Wire still in the way.
Tight quarters in here. Watch your head. That wire obviously had to come out. Most of those staples. The big problem though was those 2 joists you see in the back on the left. They are exactly where my new ones need to go sitting on the steel beam and moving them is not an option...
First two up.
One more for the back of the tank.
Need more space to work, let's take another big section of cold air return down... This picture also shows the copper pipe I ran last week. It was in the way of this job so I moved it. Would be much easier to do now with the ductwork down...
4 Up, 2 to go...
Final product (with hot air ductwork back up): 6 additional 2x10s fastened and glued together, bolted to 2 jack posted which are bolted into the concrete. Those posts are going to be annoying but I feel much better about my floor now...