Geodes in an aquarium?

[Comrade]

Has anyone tried using geodes in an aquarium? I found a bunch that I had lying around in a box from when I was younger, they seem like they would look great in the aquarium, but I just can't put them in there without checking their safety. Some of them were store bought and have felt on the back (I know these things can be expensive, but my grandma bought them years ago for like nothing at an auction so removing the felt would not be a big deal.)

What could I do to remove the felt from these and make sure they are Aquarium safe? any advice would be awesome, also, some of them are smaller ones that were from a "crack your own geode" kit, and seem like they could be safer and would look great buried in the substrate. Any ideas would be awesome thanks in advance thumbs2:

[Detroit_Doug]

That sounds like it would look great ..

I would just worry that the edges of the crystals in the geodes may be a bit sharp in places and can scratch or worse on a fish or any fins tha rub across them

Detroit Doug

[robflanker]

I wouldnt use geodes unless I knew what every component was going into my tank. Every type of rock, what it releases, what is absorbs everything.

I think they are a form of silicate, but I'm not sure what they are typically housed in and whether it would affect pH or GH/KH

[KingFisher]

The majority of geodes are formed in limestone which will raise the ph of your water. The crystals themselves, although safe, would not look good for very long as film, algae, and debris would build up on them unless they were regularly taken from the tank and cleaned. I agree they would look good initially, but unless you were keeping fish that liked a higher ph level, I would not recommend their use in your tank.

[DrNic]

I would never put geodes into an aquatic environment. Geodes are made under dry heat and pressure, and I believe most will dissolve after long time in water. At the very least you could end up with a scenario where you have medium to high concentrations of various (and perhaps unwanted) minerals getting into your water.

Moreover, if I remember correctly, the outsides of some geodes contain high amounts of copper and zinc which can also carry arsenic. It's not enough to hurt a human but I doubt you'd want it in your water.

If you do plan to try this I would definitely do a bucket test first with an air stone to keep the water moving, then after a while drop in some cheap test fish (feeder guppies or something) and see if they survive.

[MonkeyPox]

You can find fake/plastic geodes that you can place inside if you want the look.

[Comrade]

thanks for the feedback, didn't want to put in anything dangerous so I guess I'll have to find something else to do with these geodes. I don't want to pay for any fake geodes I'll proably just put something less flashy in later.

[robflanker]

If you are handy with electronics, i've seem people make their own in-gravel LED things.

Look on youtube for them

[DrNic]

If you are handy with electronics, i've seem people make their own in-gravel LED things.

Look on youtube for them
I'm not sure if they are the same thing or not but I've seen something similar where you can turn the geode into a lamp. They look really cool.

[bushwhacker]

most geodes are calcium carbonate rocks, great in a african tank not so good for others..i have one nice piece in my mbuna tank thats covered in amethyst crystals

[Algenco]

I've had hollow Quartz geodes in tanks for years without a problem, they make excellent hides