Ph Dropping Like A Rock Every Night

[Rockatteer]

Any got any ideas on why my PH would drop from 7 down to 6.2 (or even 6) every night?

It's started doing it over the last 2-3 weeks.

I bring the levels back up with Baking soda, but then it drops again over night. The huge ph swings have killed off most of my fish.

Any ideas?

 

[BenPursglove]

Any additions / changes to the tank over last 3-4 weeks (not fish)? Where do you get water for the changes? Any products that you decided to use that have never used before?

 

[Rockatteer]

Water comes from the tap which has a normal PH range of 7.2 or higher. I checked it yesterday and it was 7.4.

Only thing I've changed recently is the water conditioner I use, but that was done after this started happening.

I just noticed the tank water has a strange smell to it. Almost like a match head, or the smell you get after you blow a match out.

 

[WILDER]

What substrate do you have in the tank.
Do you have any bogwood or anything that lowers ph in the tank.
Does the tank smell like sulphur.

 

[Rockatteer]

It smells like matches, which I was thinking is more phosphor? It's not the normal rotten eggs smell of sulfur.

Here's a picture of the tank so you can see what's in it etc.

 

[kribensis12]

If it drops, and dosent raise back up w/o baking soda, I say leave it at 6.2. The fish are going through more stress by the Ph going back up. So, until you figure it out, I would leave the Ph at 6.2.

 

[three-fingers]

First of all, the pH swings themselves will have not been the cause of fish the deaths.

Fish can easily tolerate changes in pH, and do so frequently both in aquariums (especially in tanks with injected CO2) and in nature (in ponds with lots of plants).

It's possible the pH swings in your tank are being caused just by the fact that during the night there is more CO2 in the water (which lowers the pH) because the plants aren't using it.

However, if your meaning that the pH stays low during the day after dropping the night before, then it's not the plants causing the pH swing anyway and that is odd, but as I said - the pH swings themselves are not killing the fish, but may be an indication of something else that is happening.

Can we get all the info on the tank?

As in, how old is it, how often do you do water changes, what additives do you use, which fish died, how old were the fish, describe how they died and give all the water stats such as nitrate and ammonia.

 

[Rockatteer]

How would I know how they died?

Yeah the PH drops and stays low, it's only coming back up because I'm putting baking soda in.

The tanks about 3 years old, only additives used are the water conditioner at water change. Water is changed weekly, although I've been doing daily changes for the past week. Filter is cleaned once per month.

Did a full water check about 2 weeks ago and everything was happy at that time. I'll try and do another one tonight.

 

[saz326]

Do you have CO2 setup?

It could be plant related. At night, plants produce CO2 faster than they use it, and CO2 causes water to acidify. Would need to have a hell of a lot of co2 being produced though.

What is your stocking and do you have much water aggitation?

 

[petertr]

What is your Gh and Kh?

If they are very low, it can swing much more easily.

 

[three-fingers]

How would I know how they died?

How were they behaving before hand, how did they look when you found them?

What species they were and the water stats will hopefully give a lot of clues, sounds like a very odd situation right now.

For now extra water changes as your doing is the ideal thing .

Personally I would avoid adding the baking soda without being able to monitor the KH.

 

[Rockatteer]

OK, well I decided to take the extreme approach and gave the tank a good clean out.

Removed everything out of the tank, washed it all out. Gravel was filthy, filter stunk of rotten eggs, which would have been what the smell was I could smell, but it wasn't until I took the filter pads out that I got a full wiff of it.


So the tanks all clean now, with fewer plants and a stable PH and the fish appear to be happy, so I think the problem is solved.

 

[WILDER]

Rotten egg smell means there bad bacteria in your tank.
Least you give it a good clean and water change now.

 

[Rockatteer]

Rotten egg smell means there bad bacteria in your tank.
Least you give it a good clean and water change now.

Yeah it was quite faint from the tank itself. I couldn't really identify the smell, but once I pulled the filter apart it was right your face, and I could tell right away what the smell was.

But yes it's all cleaned out and seems happy for now.

 

[WILDER]

Thats good news then. I would still do a few water changes over the next few days.