I have a 75 gal tank, I trying to get it to be better balanced by adding some crushed coral. How much do I need for the Ph to be around 6.7-6.8

[Stroy15]

My tap is 200 ppm gh and 100 ph kh for a ph around 7.5.

my 407 Fluval filter does have peat moss in it which pushed the ph down to (at the moment) 6.5ish 

I have some CaribSea aragonite and I am looking for advice on how to measure what kind of kh I would get per pound of crush coral before I trial and error it.

Edited August 24, 2022 by Stroy15

[CJs Aquatics]

Perhaps if you have an empty container of some sort lying around you could run a test in that? I would fill it with tap water measuring volume, test the tap water, then add some of the elements from the original tank as well as the coral, and test it daily until you see where your parameters lie when they stop fluctuating. It might give you a bit of an indication of what the coral is actually doing to adjust your water without having to adjust and readjust in your main tank as well as how long it takes to get where you desire it.  It won’t be 100% accurate because there are other factors involved however it might give you some numbers to go by as well as an idea of how much you need to do what you want to do without shelling out a bunch of extra money. I suppose the cons would be it’s not a “today” solution. Aside from that if I understood your question correctly, I feel the best way to measure what kind of kh you get from adding the aragonite would be to try it at a much smaller volume then your 75 gallon then adjust amounts to suit your specific needs.

[Mmiller2001]

Adding crushed coral will not balance your tank. Quite the opposite actually. I would keep the tank at 6.5.

[nabokovfan87]

title: Adding crushed coral
post: Adding peat moss and aragonite (and more aragonite aka crushed coral)

I'm really confused at what your goal is.

A. What species do you plan to keep in the tank?
B.  What is your actual tap water and off-gas tap water results for PH, KH, GH, Ammonia, Nitrates.

On 8/24/2022 at 11:41 AM, Stroy15 said:

My tap is 200 ppm gh and 100 ph kh for a ph around 7.5.

my 407 Fluval filter does have peat moss in it which pushed the ph down to (at the moment) 6.5ish 

I have some CaribSea aragonite and I am looking for advice on how to measure what kind of kh I would get per pound of crush coral before I trial and error it.

With Aragonite, you're basically a full salt water tank at 8.5 PH.  You definitely don't need Aragonite in this tank.  I would recommend using normal sand or keeping African Cichlids (or other high PH fish)

Stability in the tank is likely going to only happen by removing the peat moss and letting the tank balance to normal parameters.  Your KH is likely going to go from ~100 ppm up to 200-250 with the substrate. Your PH will likely go from 7.5 up quite a bit.  You GH doesn't really matter, but it'll go up as well.

I would test your water for off-gassing, meaning, test it from the tap, aerate that sample for 24 hours, report any changes in the above mentioned tests.

Then, compare that to what your tank is actually going to be sustained at.  You have a week where the moss stops working and you're looking at a devastating PH hike which will kill a lot of fish.

Edited August 25, 2022 by nabokovfan87

[JettsPapa]

I agree with @nabokovfan87.  We could help more if we knew what you plan to stock the tank with.

[Patrick_G]

I'd also leave it at 6.5. Water changes and natural fluctuations will bring it to 6.8.