Water Question: Low KH / PH Drop

[FIU Panther]

I've started monitoring my water a bit more closely as I plan to eventually setup a 125g Oscar tank that will need larger water changes than what I do on most of my tanks (25-40% weekly-biweekly) and have a concern.

I have a KH of 3 and a GH of 4-5, water comes out of the tap at around 8.2-8.4 and settles to 7.2 if I aerate it in a bucket overnight.

I've been attempting to do a fishless cycle on a 75g instead of using cycled media to see how quick I would be able to perform it. After a few weeks of no change I added some cycled media and noticed no change, which made me concerned. I tested the water and the ph was 6.0! PH is one of those things I never test. Could this be affecting the cycle? I'm assuming this low ph is due to the added ammonia and the low buffer capabilities of my water?

My question is, should I add some crushed aragonite in a small media bag to increase the buffering capabilities in some of my tanks? I'm worried about water changes using tap water being too much of a ph change for the fish. Roughly, what percentage of a water change should one be concerned about when your tap water's ph is significantly higher than your aquarium?

Regarding the tank with the fishless cycle experiment. Am I correct to believe the 6.0 ph has completely stalled the cycle?

 

[tlindsey]

I've started monitoring my water a bit more closely as I plan to eventually setup a 125g Oscar tank that will need larger water changes than what I do on most of my tanks (25-40% weekly-biweekly) and have a concern.

I have a KH of 3 and a GH of 4-5, water comes out of the tap at around 8.2-8.4 and settles to 7.2 if I aerate it in a bucket overnight.

I've been attempting to do a fishless cycle on a 75g instead of using cycled media to see how quick I would be able to perform it. After a few weeks of no change I added some cycled media and noticed no change, which made me concerned. I tested the water and the ph was 6.0! PH is one of those things I never test. Could this be affecting the cycle? I'm assuming this low ph is due to the added ammonia and the low buffer capabilities of my water?

My question is, should I add some crushed aragonite in a small media bag to increase the buffering capabilities in some of my tanks? I'm worried about water changes using tap water being too much of a ph change for the fish. Roughly, what percentage of a water change should one be concerned about when your tap water's ph is significantly higher than your aquarium?

Regarding the tank with the fishless cycle experiment. Am I correct to believe the 6.0 ph has completely stalled the cycle?

Rocksor
duanes

 

[Rocksor]

Raise the KH to at least 4 degrees, use baking soda to raise both KH and PH. I prefer this method since you can easily measure it out and know how much to add during a water change. The closer you PH is to 7, the quicker the cycle is. You tap water would be great for soft water fish and heavily planted tank. No Africans

PH is not changed linearly, so adding 1 gallon of pH 8 water to 1 gallon of 6 PH water doesn’t give you 2 gallons on ph 7 water. It goes up on a logarithmic scale when

 

[DThompson]

Nitrification bacteria (the beneficial bacteria) start to die off below 6.0 pH. So that definitely could be a reason for your cycle not going quickly.

 

[FIU Panther]

Raise the KH to at least 4 degrees, use baking soda to raise both KH and PH. I prefer this method since you can easily measure it out and know how much to add during a water change. The closer you PH is to 7, the quicker the cycle is. You tap water would be great for soft water fish and heavily planted tank. No Africans

PH is not changed linearly, so adding 1 gallon of pH 8 water to 1 gallon of 6 PH water doesn’t give you 2 gallons on ph 7 water. It goes up on a logarithmic scale when

Would adding crushed coral in filter bags help in stabilizing the PH in the tanks?

I feel like using baking soda would only work if I start treating all my water for water changes in separate containers and aging them over night. If I were to add the baking soda as I was filling it would be difficult to gauge. Am I correct that to use baking soda correctly I would have to fill my 55 gallon water drum and treat that and then use that treated water for larger water changes?

The only tank I'm worried about is the future Oscar tank as I'm sure it'll need larger than 50% changes. My 125g clown loach tank has been receiving 25%-40% changes once a week for over a year now with no negative results that I have noticed.

Should I consider adding a small bag of crushed coral behind the matten filter in my clown loach tank now as a safety measure to help buffer the water between the weekly changes?

 

[esoxlucius]

Would adding crushed coral in filter bags help in stabilizing the PH in the tanks?

I feel like using baking soda would only work if I start treating all my water for water changes in separate containers and aging them over night. If I were to add the baking soda as I was filling it would be difficult to gauge. Am I correct that to use baking soda correctly I would have to fill my 55 gallon water drum and treat that and then use that treated water for larger water changes?

The only tank I'm worried about is the future Oscar tank as I'm sure it'll need larger than 50% changes. My 125g clown loach tank has been receiving 25%-40% changes once a week for over a year now with no negative results that I have noticed.

Should I consider adding a small bag of crushed coral behind the matten filter in my clown loach tank now as a safety measure to help buffer the water between the weekly changes?

I have non existent buffering capacity, pretty much like you, and my PH out of the tap is about 7.0. A couple of days after a water change and my PH could be yellow on the API chart, which is getting into the territory of effecting your BB production. I'll add here that my tanks are both on the overstocked side.

However, this is a while back now, i've since introduced crushed coral into both my 180 and 360. Nowadays, on water change day, my PH will typically be mid 6's, which is a vast improvement on what I was getting a couple of years ago.

Beware though, don't do what I did and just put your bag of coral in and forget about it thinking it'll do the job forever. It dissolves over time and your PH will start creeping down again. Check it every once in a while and top up the bag if needed.

 

[Rocksor]

If you know how much baking soda to add per gallon of water that sat out overnight, you can easily calculate how much is needed for a tank as you refilled it.

 

[FIU Panther]

Thank you guys, I'll add some bags of crushed coral into all the tanks. Those that don't need large water changes should be good with the addition.

I'll use baking soda when I prepare water for larger water changes when the time comes.

Does anyone know the right baking soda dosage to raise KH? I've seen one teaspoon per 5 gallon, but it doesn't state how much it will raise it. I would think I only need to raise it 1 - 2 so that I don't get a massive crash if I happen to miss a water change.

 

[Rocksor]

Thank you guys, I'll add some bags of crushed coral into all the tanks. Those that don't need large water changes should be good with the addition.

I'll use baking soda when I prepare water for larger water changes when the time comes.

Does anyone know the right baking soda dosage to raise KH? I've seen one teaspoon per 5 gallon, but it doesn't state how much it will raise it. I would think I only need to raise it 1 - 2 so that I don't get a massive crash if I happen to miss a water change.

KH of 4 degrees will require weekly water changes. The weekly biological process will reduce KH by at least 1 degree in a low KH tank like yours.

 

[Ardiej]

Can someone help me , I did a clean and water chance 5 days ago and my ph is at 6 or lower , the water out of my tap is around 7-7.5 ( where I want it ) , but my tank ph won’t go up to that , I even did another water change trying to get the ph up and it didn’t do anything . A whole bottle of api ph up and it didn’t raise even a little . What do I do