Need help with my water

[SDROBBIEFISH]

Hello all! Need help. I just started my tank I put live plants, dragon rock, and Driftwood in a 9 gallon fluval flex. I'm doing test and my ph is about 6.6-6.8 my kh is little too none and my gh is high. I live in San Diego and the water here is hard. I was thinking about putting crush coral in my filter media but I'm worried that it will raise gh. What should I do. 

[Ken Burke]

Your water is similar to mine, and I use crushed coral in my discus tank without issue.  What kind of fish do you want to keep?

[SDROBBIEFISH]

I'm thinking about guppies and some bottom feeders. 

[frogdog]

I’m having the same issue in Chattanooga, TN. My pH is 6.4 (lowest the test strips will measure), my KH is 0, and my GH is the highest the test strips will measure. I’m not really sure what to do.

[Rube_Goldfish]

@SDROBBIEFISH, @frogdog: this would probably get more response in the General Discussion subforum. @Streetwise, can you move it?

That said, crushed coral should raise your KH without affecting your GH (I think; I'll caveat that I've never used crushed coral myself). That rise in KH would indirectly cause your pH to raise, too, albeit slowly.

This ACO video is a couple years old but still good:

And it looks like you've got a good grasp on pH/GH/KH, but just in case you (or any lurkers) would like a primer:

[nabokovfan87]

On 3/4/2023 at 6:06 PM, SDROBBIEFISH said:

Hello all! Need help. I just started my tank I put live plants, dragon rock, and Driftwood in a 9 gallon fluval flex. I'm doing test and my ph is about 6.6-6.8 my kh is little too none and my gh is high. I live in San Diego and the water here is hard. I was thinking about putting crush coral in my filter media but I'm worried that it will raise gh. What should I do. 

 I have similar water.  What is your GH now?  Mine is always 300+ here in socal.

KH is 40-100 depending on location.  Right now mine is 40 ppm and I buffer it up using seachem alkalinity buffer.  Coral in the filter works. I would suggest starting at 1/2 lb if you can get that much to fit.  You'll likely need more.  If you have white substrate or don't mind it on the substrate mix, then go ahead and put it there instead so you can add enough.

I recommend small scale tests in a 5g bucket, give it a few days with an airstone and go ahead and verify what's going on with the water after adding CC.  If you don't want to add it into the substrate, then I'd recommend looking into the alkalinity buffer method.

[Sora]

other than crushed coral, an alkaline buffer works very well to raise ph and kh. crushed coral and alkaline buffer are basically the same thing but just if you want options. but alkaline buffer's do not raise gh.

Edited March 9, 2023 by Sora

[Mmiller2001]

Crushed coral raises both GH and KH and specifically raises the Ca component of GH.