Is lichen on rock safe for the fishtank?

[dud]

I picked up a rock from a trip somewhere (and it is not something that will dissovle). They look cool, but I see that there are plenty of lichens that had been growing on them. They're dormant, but I think they'll become active once they get wet.

Is it necessary to eliminate these things? The problem is that they're really tough, and I pretty much doubt that I'll be able to scrub them off or anything.

Thanks.

 

[frshwaterfinatc]

Well, I have just had a bad experience with rock not from the LFS. My fiancee had this whole box of rocks from all over the country. They were all unique in some way, and I thought a good display would be to put them in my planted tank and in my fishbowl with my red-clawed crab. I rinsed them thoroughly, and then placed them in the bowl and aquarium. Bubbles fizzed out and made the water a little cloudy, but I accepted this as air moving out as water saturated the rock. The next morning, I went to feed the crab and he was dead. The water was cloudy, and it smelled like dark mud or minerals... a thick, earthy smell. It was absolutely putrid to say the least. I removed the crab and he reeked just as the water. I knew it was the rocks... and just to further test this thought I removed a rock from the aquarium and it smelled the same. The fish in the tank looked ill, too. I immediately took all those rocks out and did a 50% water change.

My caution to you is to avoid all rocks you find. Stick to store bought, professionally pre-treated decor. I lost my 3 1/2 inch red-clawed crab to rocks. Red-clawed's don't usually get that large- it's a huge loss to me. Luckily my tank didn't suffer the same way due to the larger water ratio.

 

[dud]

I asked my friend and he says the rock is rhyolite, inert igneous rock. Hmm, that makes me think that the rock itself would be pretty safe to put in the water. However, I think the stuffs that's not part of the rock, stuff that accumulated or attached itself to the rock might present problems. And I have no idea how many microscopic cracks there are that can be keeping some nasty stuff in it.

For the lichens, I found out basically soak them, activate thus soften them, and scrub them off. However, for the embedded stuff... Maybe I should autoclave them? I don't know. I'm gonna put it in the water and watch it for a while.

 

[TankGirl]

If you have access to an autoclave, that would be ideal, assuming these are solid rocks without fissures in them.

As far as the lichen goes, it would not survive completely submersed, and would eventually die off and depending on how much was there, it could foul the water a bit but I don't think it would be harmful in and of itself.

I have cooked rocks on the grill and scrubbed them since I had a bunch and did not have pots big enough to boil them, and that worked great.

 

[liquidelusion]

i think boiling it would help. thats what i have done to small rocks/shells that i put in my tank