120 gal Paludarium build with grey foam

pleh · #1 05-06-2010, 08:23 PM

I finally finished (well, is one ever really finished) my conversion of an old 120 gal plexi salt tank into a crested gecko paludarium setup, using grey polyurethane foam rubber.

Background: I have been using the foam inserts from LLL Reptile in 12x12x18 and 18x18x24 Exo-Terra tanks and have been really pleased with them, so I decided to use the same material on this rebuild. The first thing I tried was to get the manufacturer of those inserts to do the custom sizes I needed, but no luck. It is definitely better to just buy the finished inserts than make them yourself, if you can work with the sizes they make. The foam pieces are not cheap and it is time consuming to cut and sculp them, and his sculpting and painting are really good.

The tank is an old drilled plexi 5'x18"x24" drilled system that I have had set up as a salt tank for the last 25 years. It was originally set up as a reverse flow system, where the water is pumped up through the undergravel filter and flows into the built in back wet/dry filter and then back into the tank. It also already had a Fluval 403 canister filter, so I incorportated that into the build as well. I reversed the flow on the main pump so that the water goes down through the undergravel filter and is pumped into the back chamber, then it flows out through what used to be the skimmer part of the chamber. The Fluval is plumbed to suck in at one end of the water area and shoot out at the other end, with valves to manually switch to a spray bar at the top, or a hose for washing down. The Fluval did not have enough pressure to use the sprinkler heads that I originally tried, so I switched to a 1/2" pipe drilled with holes for a spray bar. It can be slid easily and rotated in its brackets to better cover the tank.

pleh · #2 05-06-2010, 08:31 PM

Carving the foam.
It is usually used for seat cushions, and is springy and stiff.
It cuts pretty easily, since I couldn't find a big enough bandsaw to cut the block with I purchased a machete for the straight cuts and used a fine hacksaw blade shoved into a piece of plastic pipe for a handle for the curves.

I sculpted the foam in two main ways, grabbing pieces with pliers and pulling them off, and grabbing pieces with my fingers and tearing it off. Any straight cuts done with a knife look artificial, so the tear method ended up being the best way. A power wire brush did not give the right texture.

pleh · #3 05-06-2010, 08:38 PM

Inserting the foam. This would have been a lot easier with a glass tank with a totally open top, and I would have definitely carved out of one piece of foam instead of piecing 4 together. The foam is resting on a layer of egg crate with a one square edge banded to it with ties. I also inserted sticks down through the foam and tied it through holes drilled through the back filter to hold the foam firmly against the back. I then used E-6000 to glue the foam pieces together at the seams, as I didn't like the obviousness of the joints.

pleh · #4 05-06-2010, 08:46 PM

Plants. I installed plants by cutting an x into the foam and inserting the root ball. I rinsed all root balls completely to try to get rid of all soil. I have a cork tube on order and I'll figure out where it'll go after it arrives. The tank got crowded very quickly.

I was planning on painting the foam, but after the test installation, my wife really liked the base grey color- it looks just like grey lava rock, so we left it unpainted.

Had to drill a lot of holes in the plexi tops- the tank steamed up on the inside to the point where you couldn't see into it. I might have to install a small fan somewhere if there is not enough ventilation.

froggsong · #5 05-06-2010, 11:38 PM

Looks nice. I've thought about using some foam like that. I really like that you left if grey. Are you going to grow moss on it?

pleh · #6 05-07-2010, 04:49 AM

Quote:

Originally Posted by froggsong

Looks nice. I've thought about using some foam like that. I really like that you left if grey. Are you going to grow moss on it?

Possibly. I have some moss tucked in on one of the streams up top, will see how it does. I also need to decorate the water area more, probably get a piece of malaysian driftwood and some water plants in the next week or so.

The crested geckos actually make quite a mess, so this tank is set up to try to make it as easy as possible to clean. We'll see how well that works out in a month or so.

Epiphile · #7 05-07-2010, 06:34 AM

I really like this build- you did a good job on the background. How do you find the water's moving downward? Is it travelling through the foam as well as over it?

beckdg · #8 05-07-2010, 08:08 AM

seat cushions... not bad! it came out looking really good.

Grimm · #9 05-07-2010, 10:47 AM

Cool build! Looks saweet! Nice idea with the cushions. How much $ for a piece that size?

pleh · #10 05-07-2010, 12:00 PM

Quote:

Originally Posted by Epiphile

I really like this build- you did a good job on the background. How do you find the water's moving downward? Is it travelling through the foam as well as over it?

The biggest advantage to this construction method is that the foam acts like a big sponge filter- the water is flowing down through the foam hopefully allowing for the development of the proper nitrosomas/nitrobacter bacteria to form. Normally the waterfall areas get a coating of silicone to keep all of the water from absorbing, but with the huge amount of flow I figured there would be enough to skip the silicone, and so far there is. On every one of the precarved tanks I have set up I wish I had put in a bigger pump as over time more and more water seems to soak into the foam and some of the smaller waterways, even with silicone, have dried up and no longer reaches the bottom of the waterway. On this build the back filter is completely filled with water, so any little holes drilled through it, like the ones I drilled to tie the foam to the back, allow to flow into the foam. On the other tanks I definitely have to water plants high on the foam, on this tank I think every area will get enough water for the plants without watering.

Those blocks cost $30 each. I had to go to a foam distributor to get it (a 250 mile roundtrip, shipping was going to be $90)- they carve your order off ofhuge block of it, so you can get pretty much any size and thickness. Since they had a $100 minimum, I got 2 12x12x18 blocks to round out the order and I'll use them in future tanks. You also have to make sure it does not have the fire resistant treatment.

Again I'll reiterate- buying the finished inserts is definitely the way to go if you are doing a tank in one of the standard sizes they offer. I think they charge $40 for a 12x12x18 one and $60 for an 18x18x24, and at those prices, he's working cheap.

BTW, the foam is pretty tough stuff, about as tough as a kitchen sponge, so any dried poop is pretty easy to get wet and a finger scrub takes it right off without damaging the foam.

We'll see how well fish will do in the bottom. I've had trouble even keeping bettas alive in the other tanks, but I think that is due to the large amount of gecko waste and the small amount of water just overwhelming any bacterial filtration. With this large tank I am hopiing that the increased water amount will let me have some fish in the bottom. I'm hoping for mudskippers or Anableps, but I haven't seen any of those for sale around here in decades.

Damn, now I want to build another one. One of those really wide corner tanks with an island in the middle would be really fun to design.