Spray foam background? Edit: documenting my tank build here!

[JamieL]

I'm setting up a 55 and I'd like to build a foam climbing background. I'm concerned about the foam insulating the heat from a UTH OUT instead of IN. How would such a background affect heating, and how would I solve the problem?

[Hermias_mom]

So what type of foam are you planning to use? Sprayable polyurethane? Foam board? Some other type? IMO foam is not a good choice because the crabs will tear it up and eat it. What's the blowing agent (residue gets left behind)? What impurities are in the foam (a lot of these are toxic)? Does it have any plasticizers to make it flexible? Those can also cause an issue.

Because foam is not a food, info on impurities and constituents and trace residues may be trade secret, and very hard to find out. And things that might not bother a person (and therefore not be reported on Safety Data Sheets) might be toxic to crabs. In my opinion, foam is only suitable for insulation on the OUTSIDE of the tank, where the crabs can't get to it.

Side note: If you're using canned foam (sprayable foam), make VERY SURE to read and OBEY the safety cautions. Some of these foams have ingredients in the uncured state that can seriously mess you up. And ALWAYS make sure your foam is fully cured before letting people be around it. Some times this can take weeks, and elevated temperatures can help post-application. You do not want to breathe the blowing agent or be around any uncured foam.

Foam is a very good insulator. It will basically block heat input if you put it directly against a tank wall. When you have foam outside the tank, sandwiching you UTH to your tank wall, aluminum-foil-wrapped foam is a great thing, because it direct heat into the tank, and prevents it from escaping into the surrounding room.

Instead of foam for a climbing wall, I'd suggest using cocofiber matting or coconut hull fiber, or building something using aquarium safe silicone as glue. Even legos would work. Other options include cork rounds and bark, beach tree rounds, genuine fishing net, etc. Any branches from the safe foods list (no pesticides, herbicides, etc).

Basically, if it's not on the safe foods list, and you plan to put it in the crabitat, best practice is to make sure the crabs can't tear it up and eat it. They will sample everything, it's just their way. Their pincers are very strong.

I prefer polyethylene plastic for structures in my tat. Or hemp rope (which is tough, but edible). Polyethylene is a food-safe plastic that doesn't corrode or degrade in the presence of saltwater, and is sturdy enough to do a lot with structurally. It also comes in a lot of different shapes. Aquarium plants are also usually a nice touch.

Best of luck!

[JamieL]

So my plan was to work off this tutorial: http://www.neherpetoculture.com/custombackgrounds

It uses spray foam, coats that with silicone and covers the silicone in coconut fiber. My plan was to make some climbing areas, a little built in cave and stick in a few hardscape items, like little wood pieces or this small aquarium ornament I have

I contacted the company that makes the foam to ask them about it. What do you mean when you say you use polyethylene for structures? Is it a type of plastic you're checking (like the plastic number), or is there some kind of material you use for building things?

[aussieJJDude]

Well you could spray foam areas that wpnt be in contact with the UTH or consider positioning the background a few inches off the wall so heat is allowed through.

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[JamieL]

Well you could spray foam areas that wpnt be in contact with the UTH or consider positioning the background a few inches off the wall so heat is allowed through.

Sent from my SM-G935F using Tapatalk

That's an idea, I could do a partial background and leave open glass for heat transfer. I wonder if it's set away from the glass someone might crawl behind it and get themselves stuck

[Hermias_mom]

So my plan was to work off this tutorial: http://www.neherpetoculture.com/custombackgrounds

It uses spray foam, coats that with silicone and covers the silicone in coconut fiber. My plan was to make some climbing areas, a little built in cave and stick in a few hardscape items, like little wood pieces or this small aquarium ornament I have

I contacted the company that makes the foam to ask them about it. What do you mean when you say you use polyethylene for structures? Is it a type of plastic you're checking (like the plastic number), or is there some kind of material you use for building things?

That's a pretty awesome tutorial! How cool! Great Stuff is the kind of foam I thought you might be talking about. Err on the side of caution with the curing time (longer the better), and don't apply it too thickly, and you should be fine. I'd recommend reading the manufacturer's application instructions as well, since cure time is influenced by the temperature of the foam and the room where it's curing at.

I'd still keep a pretty close eye on the crabs in case they decide to tear into your structure. Never quite know what those little guys will do.

The UTH usually doesn't cover the entire back of a tat. In fact, you can put it on one end if you like. I'd recommend that wherever your UTH touches the glass, the spray foam structure doesn't. Does that make sense? That's so the UTH can radiate through the glass and heat the tat air. You could connect your structure to the glass above the UTH, and then come down in front of the UTH away from the glass until you meet the substrate, kinda like a waterfall or a ramp, but solid.

Polyethylene is a type of plastic. You can get it from McMaster Carr (for instance) in blocks (such as https://www.mcmaster.com/#polyethylene- ... s/=18sata1 ), and then machine it on a lathe or bandsaw, or by hand, if you're so inclined. Be aware, it's very smooth, but you can abrade it to give it a texture easily (so the crabs can climb it). Also it may be pretty hard to bond things to it, but it's easy to mechanically attach stuff to it. It's the same type of plastic that plastic craft mesh is made out of. You do however want to keep the temperature while it's being machined to below about 120F or it will soften and melt from the friction from cutting.

Looks like a cool project! Good luck!

[aussieJJDude]

I also reccomend once cured to remove the outer smooth layer as i heard from viv people that silicone doesnt stick that well to it.

Sent from my SM-G935F using Tapatalk

[JamieL]

So my plan was to work off this tutorial: http://www.neherpetoculture.com/custombackgrounds

It uses spray foam, coats that with silicone and covers the silicone in coconut fiber. My plan was to make some climbing areas, a little built in cave and stick in a few hardscape items, like little wood pieces or this small aquarium ornament I have

I contacted the company that makes the foam to ask them about it. What do you mean when you say you use polyethylene for structures? Is it a type of plastic you're checking (like the plastic number), or is there some kind of material you use for building things?

That's a pretty awesome tutorial! How cool! Great Stuff is the kind of foam I thought you might be talking about. Err on the side of caution with the curing time (longer the better), and don't apply it too thickly, and you should be fine. I'd recommend reading the manufacturer's application instructions as well, since cure time is influenced by the temperature of the foam and the room where it's curing at.

I'd still keep a pretty close eye on the crabs in case they decide to tear into your structure. Never quite know what those little guys will do.

The UTH usually doesn't cover the entire back of a tat. In fact, you can put it on one end if you like. I'd recommend that wherever your UTH touches the glass, the spray foam structure doesn't. Does that make sense? That's so the UTH can radiate through the glass and heat the tat air. You could connect your structure to the glass above the UTH, and then come down in front of the UTH away from the glass until you meet the substrate, kinda like a waterfall or a ramp, but solid.

Polyethylene is a type of plastic. You can get it from McMaster Carr (for instance) in blocks (such as https://www.mcmaster.com/#polyethylene- ... s/=18sata1 ), and then machine it on a lathe or bandsaw, or by hand, if you're so inclined. Be aware, it's very smooth, but you can abrade it to give it a texture easily (so the crabs can climb it). Also it may be pretty hard to bond things to it, but it's easy to mechanically attach stuff to it. It's the same type of plastic that plastic craft mesh is made out of. You do however want to keep the temperature while it's being machined to below about 120F or it will soften and melt from the friction from cutting.

Looks like a cool project! Good luck!

Thanks! So you think it'll be ok with proper curing time and monitoring for crab destruction? I'm not in a rush, I have no problem letting each step cure for a long time, even if it takes a few weeks to finish. I'm thinking about using more sand as a top layer and embedding sand dollars and shells too, so a lot of the background is "stuff". I have a UTH on my 20g long and a small 10g size, so I suppose i could either buy a new one or position the two smaller ones in open glass space. I'll have to plan ahead before I start.

The polyethylene sounds interesting, I'll keep that in mind in the future!

[JamieL]

I also reccomend once cured to remove the outer smooth layer as i heard from viv people that silicone doesnt stick that well to it.

Sent from my SM-G935F using Tapatalk

The outer layer of the great stuff foam? So spray the foam, sculpt, then lightly sand before applying silicone?
I can do that, thanks for the tip

[Hermias_mom]

So my plan was to work off this tutorial: http://www.neherpetoculture.com/custombackgrounds

It uses spray foam, coats that with silicone and covers the silicone in coconut fiber. My plan was to make some climbing areas, a little built in cave and stick in a few hardscape items, like little wood pieces or this small aquarium ornament I have

I contacted the company that makes the foam to ask them about it. What do you mean when you say you use polyethylene for structures? Is it a type of plastic you're checking (like the plastic number), or is there some kind of material you use for building things?

That's a pretty awesome tutorial! How cool! Great Stuff is the kind of foam I thought you might be talking about. Err on the side of caution with the curing time (longer the better), and don't apply it too thickly, and you should be fine. I'd recommend reading the manufacturer's application instructions as well, since cure time is influenced by the temperature of the foam and the room where it's curing at.

I'd still keep a pretty close eye on the crabs in case they decide to tear into your structure. Never quite know what those little guys will do.

The UTH usually doesn't cover the entire back of a tat. In fact, you can put it on one end if you like. I'd recommend that wherever your UTH touches the glass, the spray foam structure doesn't. Does that make sense? That's so the UTH can radiate through the glass and heat the tat air. You could connect your structure to the glass above the UTH, and then come down in front of the UTH away from the glass until you meet the substrate, kinda like a waterfall or a ramp, but solid.

Polyethylene is a type of plastic. You can get it from McMaster Carr (for instance) in blocks (such as https://www.mcmaster.com/#polyethylene- ... s/=18sata1 ), and then machine it on a lathe or bandsaw, or by hand, if you're so inclined. Be aware, it's very smooth, but you can abrade it to give it a texture easily (so the crabs can climb it). Also it may be pretty hard to bond things to it, but it's easy to mechanically attach stuff to it. It's the same type of plastic that plastic craft mesh is made out of. You do however want to keep the temperature while it's being machined to below about 120F or it will soften and melt from the friction from cutting.

Looks like a cool project! Good luck!

Thanks! So you think it'll be ok with proper curing time and monitoring for crab destruction? I'm not in a rush, I have no problem letting each step cure for a long time, even if it takes a few weeks to finish. I'm thinking about using more sand as a top layer and embedding sand dollars and shells too, so a lot of the background is "stuff". I have a UTH on my 20g long and a small 10g size, so I suppose i could either buy a new one or position the two smaller ones in open glass space. I'll have to plan ahead before I start.

The polyethylene sounds interesting, I'll keep that in mind in the future!

One other thing to consider when curing foam is the final foam thickness. The manufacturer should be able to give max thickness recommendations in the application instructions. There's usually an exotherm (heat evolution) due to the curing process, and if the foam gets too thick (I'm thinking 8-12" or more thick in large sections (square feet sections), so it may not apply to what you're doing) then you run a risk of it catching on fire or smoldering due to excessive heat evolution during the exotherm that happens when the material cures. (Don't breathe the smoke of course if it smolders!) You can take a look at the SDS (Safety Data Sheet) that all manufacturers (in the USA at least) are required to make publically available upon request to see if the smoke would be toxic. For many types of foam, the smoke is highly toxic. Often the SDS are kept on the manufacturers website. The high toxicity of the smoke evolved from burning foam products is one reason we're counseled to exit burning buildings and homes so quickly. Just think of all the foam in your couch or bed or insulation in the walls!

Another note, more of an FYI and a suggestion: When you machine the foam, I'd keep a shop vaccuum around and vacuum up the dust as you go. As long as you're not creating a large amount of dust, you should be fine. And I don't think you'll have a problem with the amount of foam you're planning to use and sand. But I do know that in industrial situations, with a large amount of foam machining and a lot of dust buildup in the processing area or inside the vacuum cleaner, the dust can undergo combustion (spontaneously catch fire) when it's over a certain concentration.

If it were me doing the project, once I got the foam on there and sanded, I'd do a heat soak, which is where you use the UTH to heat the tank (with climbing structure in place, minus substrate) to the highest temperature you think the tat will ever see (I'd go up to about 10F-15F above the max tat temp if possible, as long as the temperature you go to is within the silicone and Great Stuff normal usage temperature range, but that's me), and let it sit for a week or so at that temperature, checking periodically to see if there are any smells. This will help outgas the foam. Then I'd apply silicone, cure according to instructions, and heat soak the tat again. After heat soaking is over and everything has cooled down I'd wipe the exposed glass interior walls with white vinegar to remove any deposited residue from the heat soak (may not be any, but I would probably try to clean it anyway). I might not be able to clean the climbing structure with the white vinegar due to it's having a rough surface, but I'd probably try. Personally I worry about fumes in the crabitat, because I rarely put my nose in there (due to mold), so I don't know what my crabs are being exposed to, and I like to try and prevent any exposures that I can control.

Sand and sand dollars embedded in the foam sounds fun! Bear in mind, sometimes crabs will try and eat the sand dollars for the calcium...

Have fun! Let us know how it goes!

[JamieL]

Thanks for the advice. I'll do the heat soak, the can says combustible above 240*F, but doesn't advise on thickness beyond stating that cure time is 8 hours but can vary depending on thickness, so I'll have to research further. (Ill cure it for at least several days, regardless) I'll be sure to wear a mask, eyewear and gloves, and shop vac periodically

The sand dollars can be a built-in snack! It'll probably look cool and eroded over time

[Hermias_mom]

Thanks for the advice. I'll do the heat soak, the can says combustible above 240*F, but doesn't advise on thickness beyond stating that cure time is 8 hours but can vary depending on thickness, so I'll have to research further. (Ill cure it for at least several days, regardless) I'll be sure to wear a mask, eyewear and gloves, and shop vac periodically

The sand dollars can be a built-in snack! It'll probably look cool and eroded over time

Having a good supply of fresh air flow is also highly recommended when using the spray foam. Maybe do it outside. I don't think you'd need a fan on it on full blast, but a moderate persistent airflow would probably be a good idea, and an outside breeze would probably be enough.

I'm sure you've probably seen it already by now, but here's the Great Stuff safety usage info. http://msdssearch.dow.com/PublishedLite ... age=GetDoc

Isocyanate exposure is no joke. One of the problems about isocyanates is, there's no smell to them, and once you develop a sensitivity, it doesn't go away, and can cause serious problems. You can be exposed to isocyanates past the recommended exposure limit before you smell the chemical, so in industrial applications breathing air is used (air that is pumped from outside where there is a clean supply of fresh air) when handling the liquid resin for the A component of the foam. Since Great Stuff is a canned product, where the chemicals mix and harden very quickly, likelihood of exposure to liquid isocyanates is pretty low, especially when the appropriate personal protective equipment is used (gloves, eyegoggles, skin coverings, particulate respirator, etc).

Not saying that you personally would, but I know sometimes in non-industrial settings folks may have a tendency to overlook or not do the safety precautions when using chemicals and materials from the hardware store (how many of us use gloves all the time when using chemicals to clean our kitchens?). Just want to be sure anyone reading this realizes that taking personal safety seriously is important when using Great Stuff or similar foam products.

As far as thickness goes, you may want to practice a bit, but if you apply a layer of foam, then wait a few seconds until it stops expanding, you can then apply another layer of foam over top of that, and it should bond fine. Layers an inch or two thick should be fine for sure. If you stop spraying and come back later, you can remove the foam skin by sanding it, and then spray atop it again if you want. Or you can spray on top of the skin. If I were doing the project, I'd just try a few things myself, and see how it adheres. Best way to remove or trim bits of foam, besides sanding, is with a very sharp knife sturdy knife, so don't forget the cut-proof gloves. It can take some force to cut through the foam.

I look forward to pictures!

[JamieL]

i started the foam today. I got some in a few unwanted areas so I'm hoping I can scrape it off with a razor. I started it tonight because my kid is at grandmas for a few days. I left it outside, hopefully it'll be ok - I didn't even want it in the garage until cured. I should have turned it on its side but I couldn't because I didn't have a second person around to help me, and I couldn't get the hardscape items to stick. There seems to be not much in between wet gloppy foam and hardened shell. I may go back with more foam, or I may attempt to stick them with silicone when I start that layer.



And yes, I followed safety procedures!

[wodesorel]

One thing that worries me about using spray foam with a heater is that at higher temps (the 240 you mentioned) is that it starts to release cyanide gas. I doubt that a malfunctioning heater could hit that, but in the event of an accident the crabs and anything else around it would be dead. It's made me second guess some Viv ideas going forward. The people who use it do it with animals that don't need heat or only need belly heat.

That's really the only downside to using it. That and it's impossible to remove once you put it on. You may think you can pull it off of glass but noooooo it bonds to it to where you can't get a Razer blade behind it. Been there done that have a half ruined tank in storage to prove it.

You kind of have to foam around what you want to stick in while it's laying flat and wait for it to cure, trim (bread knife or serated knife works wonders), and then keep going with the design. The foam falls flat if you mess with it before curing, but if you let it do its thing with gravity to help then objects get very well bonded. I used toothpicks and sticks as an understructure and then foamed it all in. Don't glue to the glass or you risk cracking it as the foam expands, just do the foam against the bare glass and if need be glue to that foam base.

[JamieL]

One thing that worries me about using spray foam with a heater is that at higher temps (the 240 you mentioned) is that it starts to release cyanide gas. I doubt that a malfunctioning heater could hit that, but in the event of an accident the crabs and anything else around it would be dead. It's made me second guess some Viv ideas going forward. The people who use it do it with animals that don't need heat or only need belly heat.

That's really the only downside to using it. That and it's impossible to remove once you put it on. You may think you can pull it off of glass but noooooo it bonds to it to where you can't get a Razer blade behind it. Been there done that have a half ruined tank in storage to prove it.

You kind of have to foam around what you want to stick in while it's laying flat and wait for it to cure, trim (bread knife or serated knife works wonders), and then keep going with the design. The foam falls flat if you mess with it before curing, but if you let it do its thing with gravity to help then objects get very well bonded. I used toothpicks and sticks as an understructure and then foamed it all in. Don't glue to the glass or you risk cracking it as the foam expands, just do the foam against the bare glass and if need be glue to that foam base.

I'll keep that in mind. I'll be vigilant about checking the heater. How common is it for heaters to malfunction? I will need to purchase a new heating pad for this tank, I assume you'd recommend an ultratherm?