# Need advice on waterproofing aquarium stand.



## Knic (Nov 11, 2013)

So I bought a stand from Petco. Reviews say that it's terrible at being water resistant, but bought it anyway because of its looks. After endless searching I only found a couple sites on any advice so I decided to make a thread on this forum. Any help is greatly appreciated. 

Stand is made of LAMINATED MDF. The laminate will be fine with water, but it's the edges I'm concerned about (though I'd like to add protection to the entire stand anyway). I read that I can use spar urethane to make the stand water resistant. Since this is also a piece of furniture I need to keep the stand pleasant to the eye as well. 

Should I lightly sand the laminate before spraying the spar urethane? 
Will this change the looks of the stand much? (I purchased Minwax Helmsman Spar Urethane Spray Satin Finish)
Any other advice?
There are probably other options out there; any other options I should consider or am I going to be fine?

Thank you in advance!


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## Dave Paine (May 30, 2012)

The manufacturers should know better, but they are selling to a price point.

MDF and water do not mix. Urethane is water resistant, not water proof. If water is left standing such as a splash dripping down and collecting between the tank and the MDF surface, moisture will migrate through the urethane over time.

If enough moisture migrates, the MDF particles will expand. I do not expect the glue in this MDF is water proof.

You can try and improve the water resistance by coating the MDF with Zinsser SealCoat. This is a dewaxed shellac which will absorb deeper into the MDF.

For the final finish an epoxy paint may provide the most water resistance.


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## Knic (Nov 11, 2013)

Dave Paine said:


> The manufacturers should know better, but they are selling to a price point.
> 
> MDF and water do not mix. Urethane is water resistant, not water proof. If water is left standing such as a splash dripping down and collecting between the tank and the MDF surface, moisture will migrate through the urethane over time.
> 
> ...


Thanks for the reply. Is this advice for laminated MDF?


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## Knic (Nov 11, 2013)

Dave Paine said:


> The manufacturers should know better, but they are selling to a price point.
> 
> MDF and water do not mix. Urethane is water resistant, not water proof. If water is left standing such as a splash dripping down and collecting between the tank and the MDF surface, moisture will migrate through the urethane over time.
> 
> ...


Thanks for the reply. Is this advice for laminated MDF?


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## HowardAcheson (Nov 25, 2011)

Let me make a couple of points. One, what do you mean about material being "laminated"? Unless it is laminated with an impervious material like plastic laminate or formica water will penetrate a wood laminate.

Second, "spar" varnish is not a good choice for anything that is in a wet environment. Spar varnish is formulated and intended for use in exterior applications where the substrate will be constantly subject to flexing. It's intended application is on boat masts and other marine spars. It's formulated to be soft and flexible by the addition of lots of oil. However, the oil makes for a less water resistant finish.

For your applicaion I would recommend an interior, oil based varnish. Interior varnishes are harder and more water vapor resistant and will be more durable for your application.


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