Need advice from people use coral rubble please

[ivo]

My ph is very unstable it drops more than 0.5 per day and sometimes close to 1. My tap water is soft KH is 3 and ph is 7 fresh off the tap. I age my water for at least 24 hours using pump and heater. Ph will raise to 8 after 24 hours. My tank is bare bottom I run air pump and have cannister filter outlet pointing up to increase surface movement. I do 30% water change every 2 days. Prior to water change tank water kh is 1 and ph is 4.5 (it could be even lower but test kit only shows 4.5 as the lowest). After water change tank water ph will raise to 6 and then the next day will drop to 5. Discus are showing all the signs of ph fluctuations.

I read that one way to stabilise ph is to use coral rubble to increase buffer. Without knowing how much to use so I only added 1/2 cup to be cautious. Tank volume is
300 liters. It has been 4 days now and I don't see coral rubble has made any difference yet.

My questions are:
1. How long does it take before you see coral rubble becomes effective?
2. In my situation is 1/2 cup too little? How much do you think i need to use?

[bluelagoon]

Try a larger WC.Up to 60-80%.It might stay a bit more stable.Crushed coral is better than bubble(larger pieces).

[JBurgo]

Ivo, if I remember right, you were using Indian Almond leaves to lower the pH because your new fish wasn't eating. Are you still using them? What's the reason you're still lowering the pH (if you are)? Is your fish still sick? The Discus are domestic, are your Angels wild? Sorry to ask so many questions, but I think people will need to know more to answer properly.

If the water is coming out of the tap at 7 and aging to 8, it seems logical that shooting for such a low pH may be destabilising your water. Maybe you should shoot for 6.0 or 6.5 where it might be more stable? Or even slowly raise the pH over time to suit your municipal water? I don't have much literal experience with holding a low stable pH, because everything I read about it said it was difficult and caused pH crashes, and that it was unnecessary.

It seems odd to be trying to raise the pH with coral after lowering it with IAL (if that's what you're doing). In my experience coral sand, Texas holey rock /driftwood, barely rate a mention with pH in my aquariums (I do discus and cichlid tanks), in the end, with the amounts we use, it's all more decorative than anything chemical.

[ivo]

Ivo, if I remember right, you were using Indian Almond leaves to lower the pH because your new fish wasn't eating. Are you still using them? What's the reason you're still lowering the pH (if you are)? Is your fish still sick? The Discus are domestic, are your Angels wild? Sorry to ask so many questions, but I think people will need to know more to answer properly.

If the water is coming out of the tap at 7 and aging to 8, it seems logical that shooting for such a low pH may be destabilising your water. Maybe you should shoot for 6.0 or 6.5 where it might be more stable? Or even slowly raise the pH over time to suit your municipal water? I don't have much literal experience with holding a low stable pH, because everything I read about it said it was difficult and caused pH crashes, and that it was unnecessary.

It seems odd to be trying to raise the pH with coral after lowering it with IAL (if that's what you're doing). In my experience coral sand, Texas holey rock /driftwood, barely rate a mention with pH in my aquariums (I do discus and cichlid tanks), in the end, with the amounts we use, it's all more decorative than anything chemical.

HI mate, this is a totally different situation now. The sick discus a few months ago has been cured and is active, alive and doing very well. It is my DT that ph fluctuations is high without doing anything to it ( not adding almond leaves), ph drops a lot by itself everyday my suspicion is due to low kh predominantly and hence looking for ways to buffer my water to stabilise ph. I have now crushed the coral rubble to much smaller pieces and let's see whether it will become more effective.

[JBurgo]

I hope someone with more knowledge talks too, but..

My KH is 35.8 (2 drops), so it's lower than yours, but fortunately I don't have the problems you're experiencing.
My water comes out at pH 7.2 and with 2-3 days aging pH 6.8, and the tank sits at 6.8.

But I will say that I do have problems with my Discus displaying pH shock if I put the water in without aging for at least 2 days minimum. Maybe there's a correlation with the low KH?

I hope the crushed coral rubble works out.

[DJW]

How are you measuring pH and KH? The two don't seem to be agreeing with each other-- it looks almost like there must be an organic acid from driftwood, peat, leaves. Or possibly one of the measurements isn't right.

[ivo]

After I crushed coral rubble into much smaller pieces for two days in a row ph maintained at 5.5. I purposely not to change water because I want to see whether crushed coral rubble has effect and it does. I won't add anymore for the time being. Will start my water change regime again and monitor ph and if need to add a little more I will. Target range is between 6 to 7 stable ph then I am happy.