Farmed live rock chemistry

RCKY · 02/04/2018, 02:18 PM

Does old live rock re-introduced to the ocean on live rock farms leach calcium at a higher rate in your aquarium than old growth live rock?
I have aquariums with Tampa Bay live rock and Florida Live rock and both have very high calcium levels.

bertoni · 02/04/2018, 02:48 PM

If it's actually old live rock, it shouldn't leach calcium at any appreciable level. It takes a calcium reactor to turn true live rock, old or new, into dissolved calcium and alkalinity. There might be something wrong with the salt mix or something else might have happened. How high is the level?

RCKY · 02/04/2018, 03:11 PM

500+, always off chart. I have had some rock for 5 years and can see them "melt" over time. Holes get bigger over time. My substrate is crushed coral.

Tripod1404 · 02/04/2018, 03:36 PM

Quote:

Originally Posted by RCKY

500+, always off chart. I have had some rock for 5 years and can see them "melt" over time. Holes get bigger over time. My substrate is crushed coral.

What is the pH? For LR to dissolve, there need to be absurdly high amounts of CO2 and low pH. And you wont be able to keep and corals or coraline algae, as they wont be able to calcify in an environment that calcium carbonate can dissolve.

RCKY · 02/04/2018, 04:16 PM

My dKH is almost always 8. Have not checked actual PH. LPS corals do well, Caribbean star corals do well. Palys and zooanthids do not grow well. I do not use high calcium salt because I have had calcium precipitate in my tank in the past. Hundreds of white 1/8" diameter spots. Takes many water changes to reduce precipitation.

bertoni · 02/04/2018, 05:20 PM

Live rock can "dissolve" or at least decrease in volume over long periods of time for a number of reasons, including certain types of bacterial or animal activity. The rate should be far too slow to make a difference, at least for most setups.

You can use a second syringe of titrant to read higher levels on your calcium kit. For the Salifert setup, that means the result would be 500 ppm plus the amount on the second syringe. A lot of salt products mix up to a very high calcium level, so your reading is fairly credible so far, even without live rock dissolving. Have you checked some freshly-mixed saltwater?

RCKY · 02/04/2018, 05:26 PM

I will check the calcium level of my new water at next water change. Do you think 500 plus calcium with dKH of 8 is detrimental to certain corals?

bertoni · 02/04/2018, 08:20 PM

No, that level should be fine. A lot of salts mix up that high. I am not sure that it's possible to have a dangerously high level of calcium, in terms of toxicity, because calcium carbonate precipitates at a fairly low level, on average.

02/04/2018, 02:18 PM	#1
RCKY Registered Member Join Date: Jun 2011 Posts: 95	Farmed live rock chemistry Does old live rock re-introduced to the ocean on live rock farms leach calcium at a higher rate in your aquarium than old growth live rock? I have aquariums with Tampa Bay live rock and Florida Live rock and both have very high calcium levels.

02/04/2018, 02:48 PM	#2
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	If it's actually old live rock, it shouldn't leach calcium at any appreciable level. It takes a calcium reactor to turn true live rock, old or new, into dissolved calcium and alkalinity. There might be something wrong with the salt mix or something else might have happened. How high is the level? __________________ Jonathan Bertoni

02/04/2018, 05:20 PM	#6
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	Live rock can "dissolve" or at least decrease in volume over long periods of time for a number of reasons, including certain types of bacterial or animal activity. The rate should be far too slow to make a difference, at least for most setups. You can use a second syringe of titrant to read higher levels on your calcium kit. For the Salifert setup, that means the result would be 500 ppm plus the amount on the second syringe. A lot of salt products mix up to a very high calcium level, so your reading is fairly credible so far, even without live rock dissolving. Have you checked some freshly-mixed saltwater? __________________ Jonathan Bertoni

02/04/2018, 08:20 PM	#8
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	No, that level should be fine. A lot of salts mix up that high. I am not sure that it's possible to have a dangerously high level of calcium, in terms of toxicity, because calcium carbonate precipitates at a fairly low level, on average. __________________ Jonathan Bertoni

02/04/2018, 03:11 PM	#3
RCKY Registered Member Join Date: Jun 2011 Posts: 95	500+, always off chart. I have had some rock for 5 years and can see them "melt" over time. Holes get bigger over time. My substrate is crushed coral.

02/04/2018, 04:16 PM	#5
RCKY Registered Member Join Date: Jun 2011 Posts: 95	My dKH is almost always 8. Have not checked actual PH. LPS corals do well, Caribbean star corals do well. Palys and zooanthids do not grow well. I do not use high calcium salt because I have had calcium precipitate in my tank in the past. Hundreds of white 1/8" diameter spots. Takes many water changes to reduce precipitation.

02/04/2018, 05:26 PM	#7
RCKY Registered Member Join Date: Jun 2011 Posts: 95	I will check the calcium level of my new water at next water change. Do you think 500 plus calcium with dKH of 8 is detrimental to certain corals?