Ph of 6, possibly lower. Should I raise it?

Hi all,
I've had a 20 gal tank for about 2 years. Ammonia and nitrite are 0 and nitrate about 20ppm. I do weekly 30% water changes. I hadn't measured my pH in a long time and today I measured it and it said 6, or possibly lower as that's that my kit will read. I have cardinal tetras, Peacock gudgeons, kuhili loaches and a honey gourami. They all seem happy but I'm wondering if I should add some crushed coral to my filter to raise my pH to about 7? Or should I just leave it as it is as a fluctuating pH is worse than a low stable PH. Will the crushed coral raise the pH too quickly or will it do it gradually? Thanks in advance!

 

There's nothing wrong with fluctuating pH as long as it is biologically induced and relevant.

Things go mostly wrong when people start interfering, oftentimes against biological relevant patterns.

pH6 is fine - leave it alone.

 

Thank you for the advice

 

Those are all species that live in acidic water in the wild (most tropical fish do), so a pH of 6, however you got there, is completely acceptable if your fish are adapted to it. Most fish are capable of adapting to a wide range of water parameters.

 

If you were trying to keep some species like mollies, platies, swordtails, guppies, or African Rift Lake cichlids, they would struggle in low pH conditions. Many species come from tropical rainforests where the water tends to be soft and acidic. If your fish are doing well, do not get too excited.

One thing you might be able to do do it add a few small marble rocks to your hardscape. Unlike crushed coral, marble dissolves slowly. Thus, it should keep the pH from dropping significantly lower, without causing pH swings.

Just do not attempt to add fish that are not suited to your water quality.

 

I hadn't measured my pH in a long time and today I measured it and it said 6, or possibly lower as that's that my kit will read.

Agree with all the advice above.

Just curious: What does it usually test at and what is the pH of your source water.

 

Yes a ph of 6 is fine for those fish. But how it got to 6 may be something to look into. Adding new fish to the tank could be a problem. As FinDin said what is the ph of your tap water? Test your tap water then let some tap water sit for 12 and 24hrs. Test at each time to see if the ph is dropping during those times. You may have to age your water. How do the fish react during water changes? Do you gravel vac when changing water?