The Planted Tank Forum banner

Help with PH crash?

2826 Views 11 Replies 5 Participants Last post by  hubble13

Hi I have An older aquarium that's been set up for about 6 or 7 years 28 gal heavily planted the substrate is echo complete with Flourish root tabs.
I have recently made some changes, replaced some rotting drift wood, moved some plants and changed from DIY to pressurized co2. These changes were made over a couple of weeks and not all at once.
A couple of days ago I woke up to the all the fish gasping for breath at the surface and the drop checker yellow I quickly did a water change and all was good. I assumed that my solenoid had not shut completely allowing co2 to leek into the tank at night.
I now shut the needle valve before going to bed.
Well today is water change day and again my amanos are flyin all over the place, so I tested the water before my water change

PH 6.4<6.0
Ammonia 0
Nitrite 0
Nitrate 5.0ppm

After W/C PH a solid 6.4
Today's municipal PH is 6.6

This even when my water supply has been running around 8.0 -8.2 ( until recently the water supply has been a predictable 7.0 PH)
My last water change I did add seachem neutral regulator to try and bring down municipal PH
Could the Neutral regulator be crashing my PH?
Is this old tank syndrome?

This aquarium has been very stable up until this point and I only tested occasionally but have changed the water every week consistently.
I was going to start E.I today but I am hesitant until I get the PH up to a 6.6 or 6.8 consistently ?
any Ideas meanderings or suggestions

P.S. The amanos seem to have settled down and the cherry shrimp were unaffected.
1 - 12 of 12 Posts
Without knowing your KH it's hard to give advice. KH is a measure of resistance to pH change.
Today's municipal PH is 6.6
This even when my water supply has been running around 8.0 -8.2
until recently the water supply has been a predictable 7.0 PH
Call your water company.. see if they have been screwing w/ the chemicals first..

Also take a bucket of muni. and let it outgas for a day and test it

Second:
A couple of days ago I woke up to the all the fish gasping for breath at the surface and the drop checker yellow
you seem to be injecting too much CO2.. which will acidify the tank obviously.

and yes check your Kh... Probably is low..
Yes Both KH and GH are low and have been constantly for about a month
Today's readings
10/3
PH 6.0
AMMONIA .25<0
NITRITE 0
NITRATE 20PPM
Drop checker bright green
KH 1
GH 1

municipal KH is 1 or less
You'd be advised to add something to add some KH back to the water. That can be a passive source like crushed coral, or something that can be dosed like baking soda. Getting KH up to 3 or thereabouts would be beneficial for a few reasons.

Your fish gasping likely isn't related to pH that I know of, but to high CO2 levels.

pH WILL affect whether your filter bacteria work, however. When the pH is lower than about 6.4, the ammonia your tank produces stays as ammonium (which the filter bacteria can't consume). At 6.0 ammonium isn't immediately deadly, but if you shut your CO2 off and the pH goes up to 7+ right before morning, that ammonium will change back to ammonia and is toxic. This is also why even if you add baking soda don't do it all at once, and when your pH is at 6.0. Do so in the morning when I suspect your pH test would read above 6.4.

Trying to keep a stable pH at very low KH values is very difficult, since there's no resistance the change.

You're not using a pH controller, are you?
See less See more
You seem have soft water up there. Keep soft water fish which most of us can't without RO.
You'd be advised to add something to add some KH back to the water. That can be a passive source like crushed coral, or something that can be dosed like baking soda. Getting KH up to 3 or thereabouts would be beneficial for a few reasons.

Your fish gasping likely isn't related to pH that I know of, but to high CO2 levels.

pH WILL affect whether your filter bacteria work, however. When the pH is lower than about 6.4, the ammonia your tank produces stays as ammonium (which the filter bacteria can't consume). At 6.0 ammonium isn't immediately deadly, but if you shut your CO2 off and the pH goes up to 7+ right before morning, that ammonium will change back to ammonia and is toxic. This is also why even if you add baking soda don't do it all at once, and when your pH is at 6.0. Do so in the morning when I suspect your pH test would read above 6.4.

Trying to keep a stable pH at very low KH values is very difficult, since there's no resistance the change.


You're not using a pH controller, are you?
Nope not using one

Thanks I will test my water first thing in the morning to see where its at. After doing some research I have decided to do something to raise the KH I am leaning toward crushed coral as I've read that baking soda can be volatile. I was looking into some of the seachem products, equilibrium,and alkaline buffer. But I don't know enough on how they work or how to use them and the information out there is very conflicting, If any one has experience with these your help would be greatly appreciated.

Thanks Hoppy, I did read that thread, my biggest concern with this situation is the swing in PH and the health of my biological filter. It is a fairly overstocked tank and I worry that the system could crash causing an ammonia spike there is a larg amount of mulm down in the substrate, now basically its just dirt witch I view as a good thing. But has the tank become so old that it simply offers no buffering capacity

You seem have soft water up there. Keep soft water fish which most of us can't without RO.
Yep the water in PDX is really soft unless they switch from the Bull Run watershed in the cascades to a reservoir near the city, which I think has a higher PH. When the rain starts they switch back Bull Run. I usually keep fish that are undemanding and can tolerate varying water perimeters. But I don't think there are many that can survive a system crash.
See less See more
Don't bother with the buffer commercial products, too expensive for what they are plus they have to be dosed each water change.

Baking soda works fine, the "problem" is it works quickly too because it dissolves quickly. You could make a few gals of solution and drip it in, but you'd have to remember to do this each water change as well.

If you're open to crushed corral, I'd go that route. This video will probably help:
https://www.youtube.com/watch?v=WxqrVX-OL2M

Good luck!
Don't bother with the buffer commercial products, too expensive for what they are plus they have to be dosed each water change.

Baking soda works fine, the "problem" is it works quickly too because it dissolves quickly. You could make a few gals of solution and drip it in, but you'd have to remember to do this each water change as well.

If you're open to crushed corral, I'd go that route. This video will probably help:
https://www.youtube.com/watch?v=WxqrVX-OL2M

Good luck!
Thanks! That was extremely helpful!:smile2:
Good luck! I'd love to have your problem, since I love softwater fish. I guess you always want what you don't have lol
Good luck! I'd love to have your problem, since I love softwater fish. I guess you always want what you don't have lol
The grass is always greener isn't it. :grin2:Id love to keep some of the more demanding species but I.m not up for the water changes. W/Cs on three tanks once a week is quite enough for me!

So my plan is to add the crushed coral to the filter, a small amount first, cut down on fertilizer and decrease water changes and see where I am in a week. the coral should be here next week.

Today's AM readings
PH6.4>6.6
ammonia 0
nitrite 0
nitrate5ppm
I didn't bother testing kh and gh as i know there probably 0>1

I'm going to test in the afternoon and PM. to see how much the PH is fluctuating, if at all.
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top