Crazy Ph Change!

[notg2009]

Hi all,
After having a pH of 7.8 for a long long time, my pH dropped to 6.4!!!!!!!!!!!!!!!!!!!!!!! (I use API MASTER KIT)

I added a rock that I had bought from a lfs to my tank and noticed a great drop in pH, so I did a water change which pulled the pH back up to 7.4, but again it went down to 6.4. Well it is obvious that the rock is the main source of H ions, but the thing is that my plants have been growing faster and my fish are much more active!!!! what should I do? should I take the rock out? I don't want to do water changes every day, but have found an increase in ammonia levels from 0 to 0-0.25 (yellow to light green). Also I think my inca snail is not very happy with the change, but I will observe him more!


Please take a look at my signature for more info on my tank.

THANKS.

 

[notg2009]

UPDATE: I checked the recommended pH for my fish and all are ok in a pH range of 5-7, so maybe it is better to have a pH of 6.4. The only problem would be with the inca snail as recommended pH is around 7-8.

I appreciate any comments.

 

[notg2009]

UPDATE: I left the stone in a bucket of treated tap water last night and checked the pH of water which was 7.6!!!!! but the pH of the tank even after a water change was only at 6.4 this morning (tap water pH~7.8). Why is the pH dropping so much?

These are the inhabitant of the tank:

FISH:
7 rasboras
5 neons
5 glow light
2 peppered corys
2 albino corys
1 inca snail

PLANTS:
Elodea/Egeria Densa
2 water lilies (grew fast recently)
2 cryptos
1 anubias

HARDWARE:
1 decoration cave (plastic?)
gravel bed
long air stone (bubble curtain)
Penguin Bio Wheel 200
Heater @ ~79F (~26)

 

[notg2009]

anyone?

 

[ddgbumblebee]

I really don't think that the rock lowered the Ph. In fact I have never ever heard of a rock lowering Ph, it should increase it actually. The Ammonia is probably from the rock seeing as alkalis in water will try to neutralise acids. Ammonia is produced when an alkali and ammonium salt are heated (seeing as your tank is tropical this makes sense.)
Overall, this explanation is a bit much but it is true; I would remove the rock from the tank as overall it is the source of the Ammonia. However, I honestly can't decipher how your Ph is lowering, unless your plants are rotting? You probably would have noticed this by now though so I think I am wrong.
Dylan
Good luck, I'm interested to see how removing the rock will affect the situation.

 

[notg2009]

I really don't think that the rock lowered the Ph. In fact I have never ever heard of a rock lowering Ph, it should increase it actually. The Ammonia is probably from the rock seeing as alkalis in water will try to neutralise acids. Ammonia is produced when an alkali and ammonium salt are heated (seeing as your tank is tropical this makes sense.)
Overall, this explanation is a bit much but it is true; I would remove the rock from the tank as overall it is the source of the Ammonia. However, I honestly can't decipher how your Ph is lowering, unless your plants are rotting? You probably would have noticed this by now though so I think I am wrong.
Dylan
Good luck, I'm interested to see how removing the rock will affect the situation.

Thanks for the reply. Here's what I did last night: 75% water change with a lot of vacuuming. I found out that there was a lot of waste under my decoration cave, so maybe that was the reason for pH drop. So everything is clean now and the rock is inside the tank as I want to see if it changes pH or ammonia levels. Will update.

Thanks. I appreciate any comments.

 

[Amunet]

I've found that whenever my pH crashes, it's b/c there is ammonia in the tank.
Your ammonia problem could be the reason for the pH dropping so much.
Hopefully the cleaning you did will fix whatever was causing the ammonia to rise and the pH will fix itself after another water change.

You could always add some baking soda to the tank if you're worried about it dropping too low. Just add a little bit at a time and then check the pH to see where it's at so you don't have to add more than you need.
Just another option for you