Let me ask again (crushed coral)

Swords and Mollies

since I did get some input, but no follow up to my questions in regards the ph. Anybody know approximately how much crushed coral I should use in my filters? And will it hurt them if a little gets in the tank?
Thank You!

1077

I may be mistaken, but I believe I remember suggesting approx. one half cup. It will not raise the pH overnight (which is good) but will take several days to begin affecting the alkalinity . You can test the water (pH) every two or three days and take note as to the rising pH. If after ten days to two weeks, the affects are still not raising the pH to something more suitable for live bearers 7.4 to 8.0 then you can add a little more. Best to place the crushed coral in nylon mesh bag or pantyhose to keep it from getting loose in the aquarium. You will need to clean the crushed coral once a month maybe longer ,when it becomes covered with silt,bacteria,and or algae or replace it. Once it becomes covered with these substances it is far less effective.
I can't remember how large your tank is, it may be possible to start with one measured cup of the coral in larger tank. As mentioned the effects will be gradual which is good.,,
otherwise sudden change in pH or alkalinity would have bad effect on fish. Give the coral plenty of time to do it's thing before adding more if needed. Always continue with weekly water changes but changes should not be too large.

Swords and Mollies

14 gallon and 29 gallon.

Oldman47

The basic principle is easy Swords and Mollies. Calcium carbonate, the stuff shells and coral are made of, will drive the pH up to about 8.0 and no higher. If you want to go that far, just put in enough to be sure that it will never run low. If your target is a lower pH than 8, you will need to experiment with different amounts. There is no such thing as the perfect amount because you and I have different water, so the tank will respond differently to each of us using the coral. If I put an ounce of coral in my filter, I could get the same pH that you would get with a cup of it. I would start quite small if I were you and work my way up to the target pH. The lower your original pH the faster the calcium carbonate will dissolve in the water. That means you get rapid large changes if you start out at a pH of 5.5 compared to what would happen if you started with a pH of 7.0.
Sorry but there is no magic number to just go to. BTW 1077 is right about needing regular water changes. They need not be small but need to always be about the same. What that does is remove some of the buffer that has dissolved in your tank water and lets the process start over again at a bit lower pH. If the timing and magnitude are consistent, you will get consistent results.

1077

It is the rapid large changes with water chemistry that occur when adding two differing sources of water that can have negative affect on fishes osmoregulatory functions. Is why I suggested small water changes as opposed to large ones.
Ideally, the expierimenting with coral would take place in seperate container and once the desired value was achieved,then this water would be slowly added through water changes to gradually allow fish to adapt. But in this case, original poster asked about placing coral in the filter. It is as Ghreed says, the effects can vary as to boosting alkalinity depending on what source water consists of. Consiidering that change water will be considerably more acidic,(tap?) I am still an advocate of water changes of no more than 20 percent ,perhaps 25 percent as opposed to large water changes. If water was being stored however, then larger water changes could be performed IF needed and makeup of water would be same /same. I also agree with Ghreed that perhaps smaller amount of coral to begin with would cause less stress to fish . It is unclear to me how fast coral will alter the chemistry but I feel it should be gradual as to happening over night.