Rocks raised pH

[Yaz]

We setup a new 32G tank with gravel. Water pH was 7.2. When we added rocks (sold as "lace rock" from LFS), the pH shot up to 8.4. To verify the rock as the cause, I put a fresh cup of RO water and tested the water before and after adding a small piece of rock and confirmed the pH went up by exactly 1.2.

Thinking that perhaps soaking the rocks would clear it up, and rather than waste the water, we just left it in the tank for a week, and then did a 100% water change.

LFS said to get BB cycle going and to focus on pH later. So we did. Just completed the cycle and pH is at 8.0. We have also added live plants since the initial setup (moneywort, Java moss and anubias nana).

Of course, the fish we are looking to add, all want more acidic water. I also know altering pH by other means is not consistent nor easy to maintain. I also know fluctuating pH kills the fish.

So.... What can I do? Can I do a large water change now that my cycle is done? Should I remove the rocks and get something else? If so what?

 

[SaraB]

I would just remove the rocks. Can you sell them and buy different ones you like? It's better than worrying about fluctuating PH.

 

[V227]

Unless the desired acidic water loving fish are wild caught, chances are they were raised in a Florida commercial fish farm, in a hard water, high PH environment.
My Oklahoma water is very hard w/ at least an 8.2 PH. I've successfully kept numerous varieties of reputed soft water only Tetras, Discus ect. with no problems.

 

[King Fisher]

I agree with V227, my pH is between 8.2 and 8.4 and I keep and have kept several so called acidic water fish. The rocks look like they are keeping the pH steady so I wouldn't worry about it.

 

[ZxC]

I'll play for the other team, get rid of the rocks.

Plant fertilizer is better suited to slightly acidic water - neutral water. Iron specifically is basically completely un-available to plants @ a pH of 8.2.

Your fish will likely prefer the softer, acidic water too.

Find new rocks

 

[goatnad]

I'm gonna agree with zxc and Sara. I have a box of that same lace rock I never use. It raised my pH to 8.4 or so, had diatoms for over a month and my plants didn't really seem to do well at all in the tank. The plant issue could have been due to something else though.

Get rid of the rocks. Way better looking stones out there that don't affect the tank.

 

[Yaz]

Thanks everyone. Will see what we can find to replace. In the mean time at least the pH is steady.