Plywood Stand Strength Question

[gatortoes]

Hey All,

Apologies in advance for the beginner question. I just bought a use 60 gallon cube and stand. Now that I have the stand inside my house I’m starting to question if it is strong enough. It is built with 3/4” plywood, no dimensional lumber bracing, and has an open back and top.

I have done a bunch of reading and it looks like this is a somewhat common build method for stands but I wanted to get everyone’s opinion before I have 60 gallons of water that could potentially come crashing down in my house. The guy I bought it from had it up and running for over a year without problems so I know it worked, but not sure if it has the safety factor to make me comfortable.

Thanks,
Gator

 

[AlexG]

Is this a DIY built stand or did it come from a manufacturer of aquarium stands? If it was a commercially sold aquarium stand it should be engineered to hold the weight of the tank. If its DIY it should also work but if you are not sure or are having concerns you could add a 2x4 frame inside the stand to make it even stronger. From pictures alone it can be difficult to judge and the best thing to do is fill the tank to 1/4 then 1/2 then 3/4 then full and at each stage check the stand stability to see if there is any wobble or movement. If the stand is moving or wobbles stop and empty the tank. Then you can reinforce the stand and try again. Don't forget to make sure the stand and tank are level before filling.

 

[gatortoes]

Is this a DIY built stand or did it come from a manufacturer of aquarium stands? If it was a commercially sold aquarium stand it should be engineered to hold the weight of the tank. If its DIY it should also work but if you are not sure or are having concerns you could add a 2x4 frame inside the stand to make it even stronger. From pictures alone it can be difficult to judge and the best thing to do is fill the tank to 1/4 then 1/2 then 3/4 then full and at each stage check the stand stability to see if there is any wobble or movement. If the stand is moving or wobbles stop and empty the tank. Then you can reinforce the stand and try again. Don't forget to make sure the stand and tank are level before filling.

Thanks for the reply. The stand is a DIY build. Build quality/finish looks pretty good, I’m just nervous of that much weight supported by only plywood.

I moved the tank out to my garage and filled it up and the stand seems pretty solid, no wobbles or movement when under load.

I think I’m going to add some internal supports like you suggested and add a piece of plywood across the back for stability just to be safe.

I’m sure the stand is fine, but I rather over engineer the thing than have a failure down the road.

 

[AdamD76]

My 65 was on a DIY plywood only stand for 8 years with no problems. Even after sitting out back in the rain for the summer it was still strong enough to stack a bunch of steel roofing on and hold up. Plywood is super strong . there is a thread somewhere with a video demonstrating how strong a plywood stand is.

 

[OldRed1]

Thanks for the reply. The stand is a DIY build. Build quality/finish looks pretty good, I’m just nervous of that much weight supported by only plywood.

I moved the tank out to my garage and filled it up and the stand seems pretty solid, no wobbles or movement when under load.

I think I’m going to add some internal supports like you suggested and add a piece of plywood across the back for stability just to be safe.

I’m sure the stand is fine, but I rather over engineer the thing than have a failure down the road.

People knock 3/4" plywood, but it is robust and stronger than most give it credit for. Check out this thread here, with more experienced reefers commenting that 3/4" plywood, when designed well, can hold more than 250 gallon tanks. Your 90 gallon should do just fine!