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what rocks?

821 Views 8 Replies 6 Participants Last post by  mindy
i have decided that i would like to have big rocks in my tank rather than the driftwood and terracotta pot that is in there. i was just wondering if there is any rocks that i can find outside that would be safe to put in my tank?

i have a 10 gallon planted tank - java fern, crypts, hornwort, and Myriophyllum tuberculatum. there is a betta and 2 tiger shrimp in there right now. i am planning on getting more shrimps. i don't know if any of that makes any difference about what rocks i can keep in the tank.

i love the driftwood but it is always coated in slim and it is yucky.

i live in newfoundland and there are tons of rocks just outside my door :) there is a bunch of slate/shale everywhere. also granite. and there is some kind of shiny silvery rock that is filled with garnets. i don't know all the names of them. i used to know, i was a huge rock collector when i was a kid and i was planning to be a geologist. oh well, life happened and now i am a teacher and i forgot what rocks are what except for the basics.

what do you think? is it possible for me to find something outside and put it in my tank?

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I would suspect that true rocks are fine. Granite especially should be absolutely fine. I would be more concerned about sharp edges, and mineral rocks. The other thing is when you find a rock you want, bring it in and boil it to sterilize any bacteria, fungus, or parasites that might be on it.

I don't have many fish, but my dad has several goldfish, he found a rock and plopped it in the tank a few days ago.

I have fire bellied toads, (hence the name FBT) and half of my tank is constructed with rocks I found. Doesn't bother them.
Just look at all that rock!
wow! that looks awesome :) i bet your fire bellied toads love it!

thanks for the info. i was planning to boil the rocks that i bring in. i can't really get any now since we have snow but i am planning the layout of my tank already!

i am not sure what the shiny silvery one is, pyrite or something that looks similar. it has garnets in it so i don't know if that means it is bad. maybe i will get some and take a picture.

thanks for your help!
It is likely a garnet schist, a nice metamorphic rock that is perfectly fine in an aquarium.

Newfoundland has some very interesting geology and you should be able to find some really cool rocks. Most any rock is aquarium safe, limestones will mess with your chemistry but everything else is quite inert and should be fine.
just boil the rocks, wash with h202, and it should be organism free. a simple test would be putting a some vinegar on the rock, if it reacts then don't use it. otherwise rocks like limestone will mess with your water chemistry. also your driftwood is only supposed to be temporarily slimy... you might want to look into that, get some sucker mouth fish, snails, etc.
thanks guys!

oh i am so excited to be able to put some of that garnet rock in my tank! :D

i don't know why the driftwood is still slimy. it was in there for so long now. i asked about it on another forum and someone suggested that i take it out of the tank and soak it and scrub it daily for about a week. i did that and since it was back in the water it has not has the same kind of slime on it. now it has white stuff on it and it is yucky. i got it from the pet store. it is some kind of driftwood from south america or south africa or something like that. the name of the wood starts with an "m". i boiled it for about 10 minutes before i put it in my tank when i first got it.

i don't think i want sucker mouth fish or snails. i was hoping to only have shrimp and the betta in there. i also live 500 km round trip from the pet store so i can't just pop in. ;) i have been wanting more shrimp for so long now but every time i am in town the store is either closed or they don't have any shrimp in. (there has been huge issues with the ferries lately and stock everywhere is down - grocery stores and everything :()
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Sounds like Mopani wood. That's the very dense one that sinks to the bottom, instead of bobbing up and down.

I got white fungus-stuff, too, but took it out and boiled it. Seems OK so far, but it's only been 3 days.... I plan to put in just a betta and maybe some snails and/or shrimp.

Let us know how yours works out...

a simple test would be putting a some vinegar on the rock, if it reacts then don't use it.

+1, if ti bubbles with vinegar then it will mess with your water hardness. This woudl be ideal for something like a cichlid tank because they love hard water, but for msot planted tanks it wold give you trouble.

Other than that you should be fine with most any rock. As long as you don't see obvious signs of heavy metals like copper.
thanks guys :)

yes, that was what it was called, mopani wood. it still has the gross white stuff on it. i already boiled it for 10 minutes but i can take it out and boil it again. i like how it looks but it is flat and doesn't really add much to the tank. i think that i will most likely take it out and keep it out once i can get some rocks.

i can't wait until i can get some rocks. i will definitely use the vinegar trick. :) i looked up garnet schist and that is what the rocks are. i am very much looking forward to getting some nice big pieces of that to put in my tank. we don't have any snow anymore so i am really tempted to try tomorrow to get some.

any suggestions on how to design the tank once i get the rocks? how many should i get? i am guessing bigger is probably better?

thanks again!
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