Can I put dead coral in a freshwater tank?

OrangeAugust · 02-19-2013, 08:31 PM

A friend of mine gave me a piece of (dead) coral for my fish tank... I'm not sure how I'm going to add that to my scape without it looking out of place in a freshwater tank, but that's another topic. My question here is that I've read that it can raise the ph levels and hardness of the water to dangerous levels for certain fish... but for other fish it would be ok. I don't have this tank set up yet but I'm planning on having a sorority of female bettas, neon tetras, glow light tetras, zebra danios, some kind of rasbora, an angelfish, nerite and malaysian trumpet snails, and julii cories and/or otocinclus catfish. It's a 55 gallon tank. Would the coral change the water chemistry to dangerous levels for any of these fish and snails? Thanks!

Ashnic05 · 02-19-2013, 08:46 PM

Hardness would be ok with snails, but most of the fish you mentioned like more acidic pH and would not dwell well in a higher pH tank. I would advise against adding the dead coral. I've known people with african cichlids to use dead coral, but they prefer harder water and higher pH.

lochaber · 02-19-2013, 08:48 PM

Coral is basically the same stuff that makes up limestone: calcium carbonate (CaCO3).

So it will raise the hardness and pH of your tank. This would be great for rift lake cichlids, but it sounds like most of your fish are softwater types. I don't know that it would make any water conditions dangerous, just probably not ideal.

Snails should be fine- they tend to do well in almost any conditions, except sometimes overly soft/acidic water can weaken/erode their shells.

Also, what's your tapwater/tankwater like? If your water is already fairly hard, the coral probably won't affect it much.

If you want to use it, but don't want it to affect water parameters, you could try coating it in a thin layer of epoxy, but that could be a bit of work for something like coral.

Xalyx · 02-20-2013, 02:58 AM

I use it. But my coral is really really old like dead for 10+ years. And it's been used in multiple freshwater tanks so it's kind of acclimated. I don't think you should have any problems, if you're really worried try soaking it for a month or so.

DBL TAP · 02-20-2013, 03:12 AM

Make sure the coral was meant for the aquarium. Some pieces are strictly decorative and are cured with formaldehyde.

Kyguylal · 02-20-2013, 04:08 AM

If should be safe. I can't imagine it breaking down quickly at all. Not enough to notice a difference. If you want to incorporate it...it's very porous. You could cover it in moss

02-19-2013, 08:31 PM	#1
OrangeAugust Algae Grower (View User Tanks) PTrader: (0/0%) Join Date: Jul 2012 Location: Connecticut, USA Posts: 83	Can I put dead coral in a freshwater tank? A friend of mine gave me a piece of (dead) coral for my fish tank... I'm not sure how I'm going to add that to my scape without it looking out of place in a freshwater tank, but that's another topic. My question here is that I've read that it can raise the ph levels and hardness of the water to dangerous levels for certain fish... but for other fish it would be ok. I don't have this tank set up yet but I'm planning on having a sorority of female bettas, neon tetras, glow light tetras, zebra danios, some kind of rasbora, an angelfish, nerite and malaysian trumpet snails, and julii cories and/or otocinclus catfish. It's a 55 gallon tank. Would the coral change the water chemistry to dangerous levels for any of these fish and snails? Thanks!

02-19-2013, 08:46 PM	#2
Ashnic05 Planted Tank Obsessed (View User Tanks) PTrader: (0/0%) Join Date: Jan 2013 Location: Portland, OR Posts: 418	Hardness would be ok with snails, but most of the fish you mentioned like more acidic pH and would not dwell well in a higher pH tank. I would advise against adding the dead coral. I've known people with african cichlids to use dead coral, but they prefer harder water and higher pH. __________________ Alive without breath, As cold as death; Never thirsty, ever drinking, All in mail never clinking. ~ J.R.R. Tolkien ~

02-20-2013, 03:12 AM	#5
DBL TAP Planted Member (View User Tanks) PTrader: (2/100%) Join Date: Apr 2008 Location: San Diego Posts: 167	Make sure the coral was meant for the aquarium. Some pieces are strictly decorative and are cured with formaldehyde. __________________

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02-19-2013, 08:48 PM	#3
lochaber Planted Tank Enthusiast (View User Tanks) PTrader: (0/0%) Join Date: Jan 2012 Location: Oakland, CA Posts: 808	Coral is basically the same stuff that makes up limestone: calcium carbonate (CaCO3). So it will raise the hardness and pH of your tank. This would be great for rift lake cichlids, but it sounds like most of your fish are softwater types. I don't know that it would make any water conditions dangerous, just probably not ideal. Snails should be fine- they tend to do well in almost any conditions, except sometimes overly soft/acidic water can weaken/erode their shells. Also, what's your tapwater/tankwater like? If your water is already fairly hard, the coral probably won't affect it much. If you want to use it, but don't want it to affect water parameters, you could try coating it in a thin layer of epoxy, but that could be a bit of work for something like coral.

02-20-2013, 02:58 AM	#4
Xalyx Planted Member (View User Tanks) PTrader: (0/0%) Join Date: Sep 2010 Location: Chicago Posts: 172	I use it. But my coral is really really old like dead for 10+ years. And it's been used in multiple freshwater tanks so it's kind of acclimated. I don't think you should have any problems, if you're really worried try soaking it for a month or so.

02-20-2013, 04:08 AM	#6
Kyguylal Planted Tank Obsessed (View User Tanks) PTrader: (2/100%) Join Date: Jan 2012 Location: Boston Posts: 319	If should be safe. I can't imagine it breaking down quickly at all. Not enough to notice a difference. If you want to incorporate it...it's very porous. You could cover it in moss