Question re Crushed Coral in the tank....Where is it going?

Ron Cliborn · Joined: 16 Aug 2007 Posts: 1

I put crushed coral on the bottom of my fish tank about 8-10 months
ago. I do frequent water changes as I have been advised. I also have
a lot of snails and shrimp.
Recently I did an extensive cleaning and it appears that the gravel
has decreased by at least a third if not a half. Can this be right? I
know that the coral has a solubility constant but I never looked it
up. Can this much be dissolving?
I use aged tap water to fill my tank. My tap water is probably the
best I have ever had. Not too hard, not too soft. No odors, Nice
taste.
So, is it more likely that I am wrong about the amount of crushed
coral I put in originally, or has a significant amount been dissolved
or other wise consumed?

Thanks
Ron Clon

Archived from group: alt>aquaria>tropical>fish>hobbist

Bill Stock · Joined: 16 Aug 2007 Posts: 217

"Ron Cliborn" wrote in message @4ax.com...
> So, is it more likely that I am wrong about the amount of crushed
> coral I put in originally, or has a significant amount been dissolved
> or other wise consumed?

I use coral in my filters to maintain my PH. It gives me one less thing to
worry about. I've probably lost about half of the volume over 2-3 years. So
I've lost less than you, but spreading out the coral on the bottom may help
break it up faster.

carlrs · Joined: 16 Aug 2007 Posts: 120

Ron Cliborn wrote:
> I put crushed coral on the bottom of my fish tank about 8-10 months
> ago. I do frequent water changes as I have been advised. I also have
> a lot of snails and shrimp.
> Recently I did an extensive cleaning and it appears that the gravel
> has decreased by at least a third if not a half. Can this be right? I
> know that the coral has a solubility constant but I never looked it
> up. Can this much be dissolving?
> I use aged tap water to fill my tank. My tap water is probably the
> best I have ever had. Not too hard, not too soft. No odors, Nice
> taste.
> So, is it more likely that I am wrong about the amount of crushed
> coral I put in originally, or has a significant amount been dissolved
> or other wise consumed?
>
> Thanks
> Ron Clon

Your crushed coral will disolve based on your KH, pH, and and GH.
Have you tested your tap water?
Your crushed coral seems to be disovling rapidly, but not this is not
unusual either depending on your tank and tap water parameters either.

Carl

Ray Ellis · Joined: 16 Aug 2007 Posts: 1

The crushed coral would be made of mostly calcium carbonate or calcite.
The tap water will have some dissolved carbon dioxide in it. It exists as
carbonic acid in water.
The carbonic acid reacts with calcium carbonate and forms calcium
bicarbonate (calcium alkalinity) and also raises the pH.
At a pH of approx. 8.2-8.3 there will be no carbon dioxide left.
You could aerate the tap water to drive off the carbon dioxide or increase
the pH to 8.2.-8.3 with some type of alkaline chemical (pH up, etc.).
Therefore there would be no carbon dioxide left to dissolve the crushed
coral.
Then again, the purpose of the crushed coral is to neutralize the carbon
dioxide of the water and produce a pH of 8.2.-8.3 anyway. The crushed coral
is doing what it is intended to do in other words. By raising the pH of the
tap water to 8.2-8.3 before placing it in the tank you would see minimal or
no dissolving of the crushed coral.
There is some carbon dioxide in the atmosphere so that would tend to enter
the aquarium water over time and dissolve the crushed coral. Also, other
acidic compounds produced in the tank would do it also, i.e. waste
decomposition, etc.

Hope this helps.
Ray

"carlrs" wrote in message @m7g2000cwm.googlegroups.com...
>
> Ron Cliborn wrote:
>> I put crushed coral on the bottom of my fish tank about 8-10 months
>> ago. I do frequent water changes as I have been advised. I also have
>> a lot of snails and shrimp.
>> Recently I did an extensive cleaning and it appears that the gravel
>> has decreased by at least a third if not a half. Can this be right? I
>> know that the coral has a solubility constant but I never looked it
>> up. Can this much be dissolving?
>> I use aged tap water to fill my tank. My tap water is probably the
>> best I have ever had. Not too hard, not too soft. No odors, Nice
>> taste.
>> So, is it more likely that I am wrong about the amount of crushed
>> coral I put in originally, or has a significant amount been dissolved
>> or other wise consumed?
>>
>> Thanks
>> Ron Clon
>
> Your crushed coral will disolve based on your KH, pH, and and GH.
> Have you tested your tap water?
> Your crushed coral seems to be disovling rapidly, but not this is not
> unusual either depending on your tank and tap water parameters either.
>
> Carl
>

pausto · Joined: 16 Aug 2007 Posts: 13

Ray Ellis wrote:
snip ...Also, other
> acidic compounds produced in the tank would do it also, i.e. waste
> decomposition, etc.
>
> Hope this helps.
> Ray
>

I have a non planted tank with bog wood. My tank crashed
regularly 5.5pH
and lower, though Baltimore water is good (7.2 aged). Then I put
one cup of crushed corral in (a bag) in the sump. Now (depending
om the
rate of water changes 30%, at 1 to 3 weeks), the pH moves from
7.5 to as
low as 7.0. Much more acceptable.

I have seven 5 year old Black Skirt Tera, Five 4 year old clown
loaches,
three 5 year old SAE's, Two 1.5 year old Oto's. Three 3 year old
Rainbow,
And a 2 year old Rubber nosed Pl*co. 75 gal(us) tank with 18 gal
sump filter,
3 gal of high surface area media, 350 gph flow.

Paul