Some guidance is needed - stalled cycle

[Oddness87]

So I'm in the middle of cycling my first tank which is a 45 gallon and there are a few things going on in my tank and need some guidance on as my thread title stated.

1. My cycle has stalled in converting ammonia to nitrogen, The bacteria is still processing the ammonia but at a much slower rate than before. The nitrite that is being produced by this is being converted to Nitrates fine and very quickly.

2. I have recently (2 weeks ago) added floating hornwort to my tank which may be boosting the nitrites to nitrates phase.

3. My PH has dropped to 6.0 or less. My tap water PH is showing about 6.8.


Yesterday 4/30 I completed a 50% water change to see if this would help the PH rise. Prior to the PWC, my PH was 6.0 or less and Ammonia was about 1ppm, Nitrite was 0ppm and Nitrate was about 40ppm.

I checked the tank this morning 5/1 and dosed the ammonia to about 3ppm and Nitrites were showing about 4ppm and I didn't test Nitrates. The PH was up to 7.2

My latest test as of 6:00pm 5/1 is as follows
Ammonia 2ppm
Nitrite 0ppm
Nitrate 30ppm
PH is 6.0 or less.

Could my Hornwort be lowering my PH significantly or should I be completing more PWC to keep my PH stable to finish the cycle.

Any guidance as to what is going on or maybe I am missing something that a keener eye may catch?

Thanks in advance to your responses

 

[jlk]

Hi! Is your tap ph after it has gassed out or straight out of the tap? This is important to know. Your tank isnt processing ammonia because your ph is way too low & you likely dont have sufficient buffers as well. Around 6.5, nitrification starts to slow. By the time your ph hits 6, it grinds to halt. Your bacteria need the buffers in your water to process ammonia as well- without them, there is no nitritfication cycle. Without the buffers, your ph crashes as well. So, it becomes a vicious cycle. The plants are having no effect other than possibily helping to process some amm & nitrite. How much ammonia have you been dosing (ppm)? What is your temp?

Start with a 100% water change using temperature-matched, properly conditioned water. Then add only 1-2ppm ammonia and we will see how things look in 24hrs. A bit more info is needed though to further help!

 

[Oddness87]

So I finally was able to tend to my tank yesterday.

The temp has been sitting at 82F since I started the cycle.

I'm in the process of rechecking my tap water PH. I just put some in a cup and will be using a spoon to help release some gasses and will be testing it tonight.

I completed a 95% water change yesterday as I had a hard time removing the last of the water. I also made sure the new water was of similar temperature (81F-83F) and was treated for chlorine/chloramine. I tested PH this morning and it is up from 6.0 to 6.6, I may need to complete another PWC if my tap PH test shows PH higher than this. What should I do if my PH in my tap is actually 6.8, should I do something to raise it or just keep a close eye and complete PWCs to prevent the PH from dropping below 6.6?

Prior to this crash I was dosing about 2ppm every few days to keep it around 4ppm overall. I should have been checking PH during the cycle but I totally forgot until it stalled.

Thanks!

 

[jlk]

The ph came up so thats an improvement! Let us know how your tap looks when you test it. Your bb took a bit of hit with the ph crash so they have to recover before they start processing ammonia again. Keep us posted!

 

[Oddness87]

Thanks! will do!

 

[Oddness87]

So I tested my PH in my tap water after letting it sit out all day and blowing bubbles into it every hour or so. I also tested my PH in the tank as well.

Tap is 6.0 to 6.4
Tank is still 6.6

Not sure if this is an accurate PH for my tap water. Should I leave the water out overnight and see if this will change anything?

 

[rotorhead22]

What kind of substrate do you have? What do you plan on stocking?

 

[rotorhead22]

Oh, also, you can measure GH and KH. These test give you a measure of hardness and your tank's buffering ability (need these to be at certain level to maintain stable pH). Your substrate and decorations can play a big part in determining KH, GH, and pH.

 

[jlk]

Go ahead & leave some tap out overnight. You will likely see similar results but its worth double checking just to be sure. Your tank is stable right now though it may need to be further addressed if your ph starts dropping on regular basis. Have you ever had your gh/kh checked? Might be worth having your lfs check them. How does your tap's ph test straight out of the faucet?

 

[Oddness87]

I have Pool Filtration Sand as a substrate.

I also forgot to mention I have some rocks in the tank as well. They was given to me by a friend who had it in their tank for quite some time. Could this be affecting my PH as well?

So far I have decided to stock some Corys and a nice school Zebra Danios.

 

[Oddness87]

Go ahead & leave some tap out overnight. You will likely see similar results but its worth double checking just to be sure. Your tank is stable right now though it may need to be further addressed if your ph starts dropping on regular basis. Have you ever had your gh/kh checked? Might be worth having your lfs check them. How does your tap's ph test straight out of the faucet?

The PH right out of the tap is similar to what had tested previously

No I haven't had it checked but I can certainly do that.

 

[Oddness87]

So PH in my tank is back down to 6.0

PH for tap water is 6.6

Time for another PWC and I will see if I can have my water tested today at my LFS for GH and KH.

 

[jlk]

Thanks! You should consider getting some crushed coral or argonite when you visit the lfs today (look in sw section). If its overly expensive, you can check online as well. I suspect your water needs a bit more buffering to help keep it stable. Keep us posted!

 

[Oddness87]

So I'm about to go off and test my water and buy some crushed coral. and had a few questions before I go.

Am I mixing the coral into my substrate or just placing it in a mesh bag?

At what point do I remove it from my tank if at all since my PH has been so low.

Will my PH stabilize once I complete the cycle or will I always need to keep crushed coral in my tank?

 

[rotorhead22]

Giant Zebra Danios and Corydoras typically require pH in the range 6.8 to 7.4. I would shoot for a pH of 7 - 7.2. Change your substrate to a mixture of 50% gravel and 50% Aragonite and then check after a day or two, what the pH reads; the more Aragonite the higher the pH. You can buy some Aragonite at your LFS (a 30 lb bag cost less than $20). This will stabilize and raise the pH in your tank since Aragonite is made small pieces of shells, which has the same mineral content that makes up limestone (CaCO3). This substrate will buffer your water chemistry and help you reach a stable pH without using additives. The Beneficial Bacteria in your tank abs fish will thank you for a stable pH.

You would keep this substrate mix in your tank permanently.

 

[Oddness87]

Alrighty!

Thanks for the input so far jlk and rotorhead22!

I bought some argonite (16lbs) and added about half the bag to my substrate and will see how much this will affect my tank and add more as necessary.

I also had my water tested and it was soft water with very low alkalinity which allows my PH to change so drastically.

Now I just have to play the waiting game to see how this changes my tank.

 

[jlk]

I suspected you had soft water. Keep us posted on how everything works out for you!

 

[Oddness87]

Just a quick update:

Tank PH is 7.4

Dosed 2ppm ammonia to see how badly my bb was set back.

Back to the waiting game...

 

[jlk]

Keep us posted!

 

[rotorhead22]

That is great to hear...as jlk said, keep us posted.