520 gallon plywood tank

  • We are currently upgrading MFK. thanks! -neo
Yep I use drylok on mine as twentyleagues said. I can't speak on the fiberglass resin though because I also use clear pond armor on my foam backgrounds. Drylok does form a nice hard coating though so I would "think" (cant say 100% sure so I would test a small scrap piece first) but I would think if you did 2-3 coats of drylok first then you might be okay to use the resin over it then.
 
All empty. I put way too much sand and gravel in that tank haha. I’m going to be making styrofoam/resin inserts this time to use up a lot of space and only have gravel of any real depth specifically where I want plants.

I have several huge dock floats I use for archery target backdrops I can use. Start with chainsaw carving outside, then I ordered a hot knife/wire kit to finish sculpting.

I’ve watched a lot of videos but have some questions if anyone reads this.


After painting the foam, can I just brush on clear fiberglass resin?

fiberglass resin will eat away at the Styrofoam, you need to use an epoxy resin or use a different foam. Depending on the foam used for your dock floats, you should be ok. I would test it though. if your set on fiberglass resin and Styrofoam, apply a coat of uv cure urethane before hand to prevent it eating away at the foam.

but yes, after painting your background you can just brush a resin on.

I have also used lots of permastone(a concrete like casting material that I consider reef/frog safe) in older builds and if that is applied over the foam, it will be just fine to apply any type of resin you want.
 
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Thanks. I’m. Itnset on anything really. I guess when I read resin, that’s just what I thought. But epoxy res makes more sense.

Are there any paints I can use that don’t eat the foam? Or best to coat it, then paint, then seal.
 
lots of paint wont eat it, but they also might not stick.
It depends on the foam. When I use xps (pink rigid insulating foam), I will spray it with an acrylic spray paint then fine tune it with acrylic on sponges before sealing
 
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Damn just seeing this man Hope everything is looking up and the tank holds ! I know you mentioned it by why do you think the leak happened again ? Just curious for my own build. Also I didnt write about any of my setbacks on my thread bc it would have been to much writing. But let’s just say I did enough sanding to give my hands and foreames nerve damage with an electric sander lol.
 
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Damn just seeing this man Hope everything is looking up and the tank holds ! I know you mentioned it by why do you think the leak happened again ? Just curious for my own build.
The center bottom on window side was deflecting/bowing slightly and a can see where water was getting past silicone.

I just finished building a exoskeleton of sorts around the entire base and although didn’t see it do anything up high, I’m reinforcing my bracing also. Using all 2x4/6/8’s.

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