Fishless Cycle, Ph Keeps Crashing

SpikeyPlant

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Hello, I'm in the middle of fishless cycling my first tank, a 28 litre in which I intend to keep a betta. I've been adding ammonia to 4 ppm daily.
For the past week or so I've been having problems with pH.
Before, it would be at 6.6 (which I suspect was due to the wood I had in there, which I have now taken out, as when I filled the tank up my pH was 7.0), but now every time almost all the ammonia is used up I notice it has dropped all the way down to the bottom reading of my test, 6.0.
At first I was doing a water change down to the gravel daily, but then I went out and got some pH up from the LFS, which on the back says it's a 15% sodium carbonate solution and claims to raise kh, a change I'm still waiting on. But the problem persists, no matter how many days I raise the pH, the next morning it's right back down at 6.0 on the test again.

I also have a question, if I raise the pH for the cycle would it have to remain raised when I put the fish in? Or would the fact that it is cycled mean I wouldn't have to?

Anyhow, my tank parameters this morning, using the API master test kit (liquid) are as such:
pH- 6.0
ammonia- 0.6 ppm
nitrites- are tricky, I can't tell the difference between the colours for 2 ppm and 5 ppm. It's one of those.
nitrates- 0 ppm

Using API test strips, kh and gh both appear to be at 0.

Lurking on the forums, I've seen crushed coral recommended but I haven't seen it for sale in my LFS, the closest I've seen is limestone pebbles being sold as decor. I can pop out tomorrow and have another look in case I just didn't spot it, but in the meantime I'd love any advice people have for this situation.

Hold on I made a typo, my ammonia is at 0.5 ppm
 

Joshuaharestad

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I'd recommend crushed coral. I'd order it online if I had to but it's exactly what you need. It will bring up and stabilize your ph. Don't change the water all the way to the gravel because it will undo any progress you've made on stabilizing ph. Have you ph tested your tap water?

My lfs keeps the crushed coral in back.

To be honest I did absolutely no water changes while cycling. Not sure if I should have been doing them but the tank wouldn't cycle. I finally just gave up and ignored it or a month and when I checked again everything was perfect.
 

Skavatar

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Your tap water must be quite soft. The nitrogen cycle produces acids that will drop your pH if you have low KH.

Get an API GH/KH test kit so you know what your GH/KH levels are.

Crushed coral or aragonite or limestone will work. Without a GH/KH test kit, you might raise your KH and pH too much.
 

jdhef

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Welcome to FishLore!

As mentioned, it appears you have very soft water. You will definitely want to raise that KH level. As mentioned you can use crushed coral (they use it as a substrate for salt water tanks),aragonite or limestone. But since you have a small tank (about 7 gallons) you can use a cuttle bone. Those are those things they sell in the bird department of the pet store for birds to sharpen there beaks (or maybe they eat them for the calcium). Any you could just drop one of them in your tank and it will raise the KH level as it dissolves. If you get a cuttle bone, make sure it is a plain white one, with no added flavors. It a shame you don't live closer to me. The smallest bag of crushed coral my LFS had was 15 pound. So I could have given 15.95 pounds.

I just posted a pretty long explanation of the problems that can be caused by a low KH. Here's a link to that thread:
Help - What Went Wrong?

One thing I didn't mention in that thread is that a low pH can actually make it impossible to cycle a tank due to the ammonia turning into ammonium, which is a terrible food source for the bacteria'
 
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SpikeyPlant

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On testing my tap water after letting it sit for a day or so, it turns out that out of the tap my pH is 6.6

Cheers to all the replies, and I will take a look at the mentioned thread.

Just wondering how much is too much with KH/pH, in response to Skavatar?

Also, I didn't find crushed coral at my LFS, but I did find crushed oyster shells, if I rinsed them properly, would these be fine or should I continue searching for crushed coral?
 

jdhef

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Nope, the oyster shells should work just fine.
 

Momgoose56

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jdhef said:
Nope, the oyster shells should work just fine.
Put about 1/4 to 1/3 cup of the crushed oyster shells in a small mesh media bag directly into your filter overflow chamber OR add about 1/2 to 1 pound of the oyster shells to the substrate on the floor of your tank. That will slowly raise and stabilize your pH so it doesn't fluctuate after water changes. The shells will also raise your KH a little and your GH a maybe tiny bit and the additional minerals (mostly calcium) will benefit your fish.
 

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