Coral sAND!!!!

[mrV]

Formed when CO2, (dissolving in at the surface and breathed out by the fish), and H2O, (correct me if I'm wrong, we have that in the tank as well), are in contact

Not so simply

When pH is under 8, only 1/400 of CO2 dissolve in water to form H2CO3. So it's quite small amount. And H2CO3 is a weak acid (Ka = 4,3*10^-7 mol/l) (When pH is over 10, reaction is dominant.)

CaCO3 to dissolve in sufficient quantities

Every tests, which I have made, have shown, that CaCO3 doesn't affect pH or GH so much as people usually want (fish-stores tell client to add some crushed shell, coral etc. to increase GH for platies, mollies...) You need alot of fishes to produce CO2 and lot of CO2 should form H2CO3, but...

(If you need to increase KH or GH, use baking soda and model gypsum).

When I have more time, I want to do some test: I put water in two pails. to both pail I add crushed shells/coral. Fill them with water and one of those pails I add CO2. I measure pH,KH and GH several times during 2 weeks. Now Im quite busy with my laboratory-works...

 

[snotirl]

im goin to change the water tomorrow also there are a lot of bits floating around to> I have 2 fluval 3 pumps and an airpump! 8)

 

[cassandra]

what sand is best for tropical fresh water fish

 

[snotirl]

well id say coral sand but i think its better to advoid look at all the trouble im goin trough!! )

 

[mrV]

what sand is best for tropical fresh water fish

Well, probably there is just sand rather than corals in natur B)

 

[Lateral Line]

Ordinary sand, (SiO2), is chemically inert. What you need to keep an eye on is the grain size, and to a lesser extent, shape. Fine sand tends to pack together and form a very dense substrate which, unless you stir it up often, can result in anaerobic bacterial colonisation which under some circumstance can poisonn fish.

I use swimming pool filter sand. Never had any trouble with it.

MrV: I do not believe further discussion of solubility product etc., will contribute to this thread. If you wish to discuss it further, PM me, don't worry about getting technical in PM's, I have a UK 'A' level in chemistry, and had Chem. as an ancilliary subject at university, (Earth Science major).