JeffLL

OMG! I am having so many troubles creating a waterwall/pool/river for my paludarium. I have built the retaining wall that holds back the 'land', and poured the LECA into the space and scooped out a valley into which the aforementioned pond and river would be laid. After lining the area with plastic I filled the area with Great Stuff foam, piled on substrate to become embedded in the surface of the foam, and pushed it around as it expanded and cured. The voids in the LECA application on the surface of the balloning foam were painted with epoxy and more LECA applied. A very organic look was achieved, but no matter how I try, I can still see the yellow foam through the voids in the LECA.

So I tried plaster. Papier mache to be exact. I had already crafted a wire frame demi-mold for the wall/pool/riverbed. I thought that I could cover the frame with plastic and lay the papier over it and voila! But, non. The frame torqued and warped as the relatively heavy plaster lay upon it. The malformed creation was perfect in every way but one. It did not fit the space, and being inflexible could not be reworked without a massive effort.

I looked up bondo, but it seems that this is potentially toxic, and the working time between too runny and too stiff as I build up the waterwall is short. The coloration is weird again, and the same issues with seeing the background would probably arise again.

I thought of clay. Real, genuine clay. This is a no brainer, really. I can even embed the LECA. However, I thought of the issue that plagues a plaster 'sculpture' in the tank. It is so rigid that a settling error as the clay bisque dries is irrepairable.

Enter polymer clay (PC). Colorful, I can loosely mix a couple of appropriate earthy tones, and still embed the LECA in this varigated sub-base. The PC cures in a oven at 265 degrees Fahrenheit. It also will soften when reheated to make adjustments.

I think I have found the solution to what ails me. Although I hate to ask, has anyone experiences problems with polymer clay?

JeffLL

AaronT

My concern with the polymer clay would be the dyes used to color it. I wonder if those chemicals might be harmful.

JeffLL

These are typically engineered as non-toxic so that they are child safe (accidental ingestion).

I wonder if that carries over to tank safe. However, I have seen sculptures made of the stuff, specifically for fish tanks (scuba divers).

Hmmmm,

JeffLL

AaronT

Yeah, I'm no toxologist so I can't say for sure. I just know that I wouldn't have the heart to use it in my tanks. I would be more likely to try with the real clay.

feistyfish

you could always check the MSDS of the polymer clay you're using for potential hazards that may carry over to your tank.

JERP

After a quick search, I found that it is not recommended for food dishes as it has a residue.

You might be better off with regular clay or the resin some people here have used.

JeffLL

I have already given up on polymer clay. The issue with toxicity seems to be prior to curing where the plasticizers are rendered inert. Contaminated utensils are hard to clean properly, and realistically most cannot withstand the heat of the curing. Since there is no way to guarantee that an item has FULLY cured, there is no way to guarantee that remaining plasticizer won't leech into the water column. I am not going to test this with a float test (does it make the fish float to the top of the water).

I have found a local potter (www.potterybyme.com) that might be able to fire a clay waterwall/pool/river I need to create for the paludarium. I already have the armature formed.

I have seen mention of molding resins, but could you be more specific JERP? How is it used?

JeffLL

LastAndroid

I don't know if this will be helpful, but since you said Great Stuff foam was good except for the color you can get it in black.
I think Great Stuff makes a can that actually comes in black, however if you can't find it you can find other brands in the pond/waterfall section of some stores.

JERP

There's lots of stuff if you search the forums for DIY background, great stuff, resin, fiberglass, etc.

essabee

You could try epoxy putty.