Safe Materials For Dyi Aquarium Projects

[rrraven]

I keep coming up with fun ideas to build for the aquaria, but am concerned about using materials that could turn out to be toxic to the fish. This forum seems like an ideal place to compile a list of what's super-safe, what's definitely a no-no, and what may be okay with certain precautions. I'm hoping with some many experienced folks out there, we can put together a great annotated list. I'm thinking for freshwater, but feel free to add anything specific to marine as well. This initial posting is FAR from definitive - it's just a starting point to get discussion going, don't hesitate to offer improvements and corrections!

SAFE
*glass
*plastic tubing (eg airtubes)
*rocks ("purified" by washing/bioling)
acrylic. Are there some kinds that are less suitable?


MAYBE?
*PVC pipes -- I know PVC pipes are often recommended as easy "caves" for shy fishies. Does this mean PVC in general is inert in the aquarium? Is it safe to just buy regular PVC stuff at the hardware store and use that?(After thorough soapless cleaning, of course).
*plastics -- depends on the type of plastic, as well as additives (paint, dyes, gunk)
*plexiglass

DANGER!
*metal
*shells, corals, marine remnants (in fw tank)
*anything that will leach chemicals into the water (QUERY: Is there any way to get some sense of whether this is happening (before killing off all your fishies!) A very basic test I use is to let a candidate material soak in a glass of water for a week or two, and then see if I am happy to drink the water. I figure if it tastes, or smells bad to me, or just somehow feels "gross", probably I should keep it out of the fishtank!

 

[IovaykInD]

I'm not sure, but I know pvc pipe is fine to use in a tank. The regular ones at the hardware store work just fine after a good cleaning with water.

 

[anvil63]

"*rocks ("purified" by washing/bioling)
acrylic. Are there some kinds that are less suitable?"

I would say that these are one of the biggest culprits when it comes to leeching chemicals into water. Many rocks such as limestone contain calcium carbonate (CaCO3). This will leech out into your aquarium pretty quickly increasing water hardness and pH. To test for this people generally use vingar. If you see bubbles thats bad. A better test isto use a stronger acid like muratic acid (hydrochloric acid, HCl). Also depending on where you live/getting rocks from many can have metallic ore in the composition of the rock. So in general I wouldn't use rocks the are overly speckily sp?, have shiny bits in them, noticeable veins of different color, or a bizarre color. The exception to rocks with lots of speckles is granite which is always inert.

Carl

 

[IovaykInD]

Yes, rocks such as limestone or marble contain a mineral called calcite(no good for a fish tank). You perform an acid test, in this case with vinegar. If it bubbles, then the rock should not be put into your tank.

I think acrylic is fine, but I might be wrong. Aren't there acrylic tanks? Obviously, if you can use acrylic to make a tank, it should be safe after a good washing.

 

[simonbrown403]

I have resently found out from my LFS thats some types of PVC pipe are unsafe (mainly black) due to the colerants they use.

You can use shells and coral in south american tanks

 

[Lateral Line]

>>> You can use shells and coral in south american tanks

No. You can use shells and coral sand in African Rift Valley tanks which are kept hard and alkaline. Most South American biotopes are soft acidic systems.

>>> many can have metallic ore

Ore minerals are normally noticeably "heavy" when compared to a similar sized stone/rock of known composition. It is a good idea to avoid overly "heavy" stones/rocks.

 

[simonbrown403]

>>> You can use shells and coral in south american tanks

No. You can use shells and coral sand in African Rift Valley tanks which are kept hard and alkaline. Most South American biotopes are soft acidic systems.

Sorry i keep doing thats, typing south american instead of african.... thanks for corecting me )

 

[rrraven]

I have resently found out from my LFS thats some types of PVC pipe are unsafe (mainly black) due to the colerants they use.

Thanks, everyone, for your feedback! The rock-suitability tests are great.

I'm still wishing there was some good way to test (non lethally!) for toxicity, of things like PVC or other plastic items. I understand there can't be a single test that's foolproof for all toxins, but it seems like there should be something that would give some indication of whether an item is leaching Bad Stuff. I'd thought it would be fun to build some lego/duplo towers for the tank in my daughter's room, for example. Or, to construct hiding places out of plastic baskets. In an emergency I did use a plastic basket for a molly nursery once, and it seemed to be fine -- but I don't know if it would have been problematic if it had been in the tank for longer. I did try the plastic "donut" rings that are part of the common toddler stacking toy, for an experiment on training our fishies to eat from one and not the other. I became convinced that these were causing problems -- though now I can't remember what made me think that! I think maybe we lost a few guppies soon after their introduction, and I blamed it on the rings. Though it might have been something else, of course.

Rrraven