Why isn't my pH stable?

[discus_newbie]

Hi. My tap water have a very low GH and KH. Before when i started the tank (3 months ago), I added crushed coral to keep african cichlids and the pH stayed stable at 7.6. But now I started to keep discus, I removed the coral (1.5 months ago), add some driftwood and my pH gradually dropping. Last week, my pH was 6.8 and now its only 6.1 or 6.0 something. I use API master kit. My GH is 4 and KH is 2. The discus's many water change is effecting my stability, how do I keep it stable with all those daily WC ? And also, what is the pH range that discus can withstand?

PS: I've read that discus fav range of GH and KH is 0-3. But its also impossible to keep stable pH at that level.

[Eddie]

Hi. My tap water have a very low GH and KH. Before when i started the tank (3 months ago), I added crushed coral to keep african cichlids and the pH stayed stable at 7.6. But now I started to keep discus, I removed the coral (1.5 months ago), add some driftwood and my pH gradually dropping. Last week, my pH was 6.8 and now its only 6.1 or 6.0 something. I use API master kit. My GH is 4 and KH is 2. The discus's many water change is effecting my stability, how do I keep it stable with all those daily WC ? And also, what is the pH range that discus can withstand?

PS: I've read that discus fav range of GH and KH is 0-3. But its also impossible to keep stable pH at that level.

Really good info here.

http://www.simplydiscus.com/library/water_chemistry/general/index.shtml


Eddie

[Chad Hughes]

How much water are you changing daily? If you are just changing a little here and there, add the crushed coral back to the tank. If you are doing large water changes (90 - 100%) daily, then stop watching Ph. What KH you DO have is being used very quickly. That's normal. It's low. Large water changes are necessary at low KH levels to maintain stable Ph. Adjusting the KH will keep the water MORE stable.

Best wishes!


Hi. My tap water have a very low GH and KH. Before when i started the tank (3 months ago), I added crushed coral to keep african cichlids and the pH stayed stable at 7.6. But now I started to keep discus, I removed the coral (1.5 months ago), add some driftwood and my pH gradually dropping. Last week, my pH was 6.8 and now its only 6.1 or 6.0 something. I use API master kit. My GH is 4 and KH is 2. The discus's many water change is effecting my stability, how do I keep it stable with all those daily WC ? And also, what is the pH range that discus can withstand?

PS: I've read that discus fav range of GH and KH is 0-3. But its also impossible to keep stable pH at that level.

[discus_newbie]

I'm changing about 20-30% daily. So I should add coral back into the filter? Would it raise the pH really fast? In Australia we're in the middle of a drought, in Melbourne, we're banned from washing the car with hose, bucket only, and not allow to water the lawn, so i'm very limited in water usage, even 30% is a significance amount to me. I'll take any suggestions. Thankyou for the replies

Also, how do I adjust the KH? Simply by adding coral?

[Eddie]

I'm changing about 20-30% daily. So I should add coral back into the filter? Would it raise the pH really fast? In Australia we're in the middle of a drought, in Melbourne, we're banned from washing the car with hose, bucket only, and not allow to water the lawn, so i'm very limited in water usage, even 30% is a significance amount to me. I'll take any suggestions. Thankyou for the replies

Adding the bit of coral will increase your KH which will in turn keep your PH stable. Don't add alot or your PH will increase alot. You need to add little by little, just enough to get your PH from dropping. You'll have to monitor the numbers until you know how much is enough.

Eddie

[discus_newbie]

Oh thanks guys. Very quick replies

[Eddie]

Oh thanks guys. Very quick replies

fast eddie, LOL

[bs6749]

You may also want to add baking soda (sodium bicarbonate) to the tank. This will increase the KH as well and it will allow you to keep the KH where you want it by measuring out what you need. You really won't be able to control the KH by putting crushed coral into the tank.

Do an experiment with a gallon of water and add some baking soda and let it dissolve and stir it through. Then measure the KH and see if you need to add more or less to get it to where you want your tank to be. Then, when you change 20 gallons of water you will know that you need to add 20 times that amount to the tank to keep it where it needs to be.

I wouldn't say that your pH is bad if it is acidic like that. I'd actually prefer it acidic over alkaline if you don't have to mess with anything to get it there. Acidic water has the benefit of inhibiting many bacterial issues that can plague discus. You should consider yourself to be lucky to have water like that! What is the pH from the tap?

[discus_newbie]

You may also want to add baking soda (sodium bicarbonate) to the tank. This will increase the KH as well and it will allow you to keep the KH where you want it by measuring out what you need. You really won't be able to control the KH by putting crushed coral into the tank.

Do an experiment with a gallon of water and add some baking soda and let it dissolve and stir it through. Then measure the KH and see if you need to add more or less to get it to where you want your tank to be. Then, when you change 20 gallons of water you will know that you need to add 20 times that amount to the tank to keep it where it needs to be.

I wouldn't say that your pH is bad if it is acidic like that. I'd actually prefer it acidic over alkaline if you don't have to mess with anything to get it there. Acidic water has the benefit of inhibiting many bacterial issues that can plague discus. You should consider yourself to be lucky to have water like that! What is the pH from the tap?

Thanks for the reply. I do realize that my acidic pH is good, but it doesn't stay like that, keep on dropping and the pop and urine pull it down with nothing keeping it up. Does this do harm? As i mention above, last week it was 6.8 and now it is 6.1 - 6.0, does this stop at a point or it will keep dropping? Some article say discus thrive at pH of 5 - 6.5, is this correct? And also at what KH and GH would the pH be stable?
Melbourne water, where I live, is extremely good, pH is constantly at 7 and KH and GH is always 3< and everyone drink from their tap. So what step should I take? I haven't add any coral and carbonate yet.

[Patr1ck]

I use ro water in my 90 gallon and the kh was 0 dKH in the tank before I started to use crushed coral. I use 3 cups of it in a mesh bag in the canister filter and now my kh is 4dKH. The best part is that once you figure out how much you need to keep the KH where you want it you dont have to worry about the coral or the ph or the KH for a really, really, really long time.

Pat

[Eddie]

Thanks for the reply. I do realize that my acidic pH is good, but it doesn't stay like that, keep on dropping and the pop and urine pull it down with nothing keeping it up. Does this do harm? As i mention above, last week it was 6.8 and now it is 6.1 - 6.0, does this stop at a point or it will keep dropping? Some article say discus thrive at pH of 5 - 6.5, is this correct? And also at what KH and GH would the pH be stable?
Melbourne water, where I live, is extremely good, pH is constantly at 7 and KH and GH is always 3< and everyone drink from their tap. So what step should I take? I haven't add any coral and carbonate yet.

Discus thrive in water with stable parameters. If you PH is dropping almost a full point overnight, thats stressing your fish out. Figure out how much coral to add or you can use baking soda instead. You need to get this worked or yoru fish are gonna pay the price. The response was given on what you need to do, there isn't much else that can be stated.

Eddie

[discus_newbie]

I use ro water in my 90 gallon and the kh was 0 dKH in the tank before I started to use crushed coral. I use 3 cups of it in a mesh bag in the canister filter and now my kh is 4dKH. The best part is that once you figure out how much you need to keep the KH where you want it you dont have to worry about the coral or the ph or the KH for a really, really, really long time.

Pat

Ok, since my tank is a 70G, I'll try adding 2 cups. Today I've just added 1 into the overhead filter, I'll add the other cup next week.
Thanks for all the replies guys

[poconogal]

I'd aim for a dkh of 4 which should be fine for keeping your PH stable. dkh of 3 is the minimum for buffering of PH, below 3, it will not buffer your PH and you will experience your PH dropping like it's been.

[bs6749]

Ok, since my tank is a 70G, I'll try adding 2 cups. Today I've just added 1 into the overhead filter, I'll add the other cup next week.
Thanks for all the replies guys

2 cups may be far more than you need. I'd do an experiment that doesn't involve your tank or fish and then scale it from those results.

[shawnhu]

http://www.dataguru.org/misc/aquarium/calKH.asp