How much of a problem is Low PH? - The Planted Tank Forum
 
LinkBack Thread Tools Display Modes
post #1 of 8 (permalink) Old 03-22-2012, 06:02 PM Thread Starter
Planted Member
 
PTrader: (0/0%)
Join Date: Jul 2011
Location: Portland, OR
Posts: 161
How much of a problem is Low PH?

cross-posting this from the Fish subforum.

I recently added CO2, and after running it for a few weeks with my rasbora's, amano's, and oto's being happy I went out and picked up a pair of GBR's w/out checking my water parameters first.

It looks like the CO2 has brought my water down to a PH of ~5.0. I'm sure this is due in no small part to the extremely soft water we have in Portland.

I've had the GBR's for 3 days now and they *appear* to be pretty happy, looking for food, coming to the front of the tank, etc.

What am I at risk of with a PH this low? Should I look into trying to correct for it or just let it go? I know crushed coral is the general means to bring it up but I don't want to add something that is going to upset the balance of things and require more additional maintenance.


Prior to cleaning/rescaping the tank and adding CO2 I was also dealing with a Hair Algae outbreak, is there any chance my Low PH would contribute to additional algae growth? I'm hoping the CO2 will keep it at bay this time but I'm definitely on the lookout for it and I've already seen a few small filaments on a couple of plants although they don't seem to be growing too much yet so I'm hoping they stay in check since I stopped dosing ferts and did some water changes.

Any advice is much appreciated.
U2Kent is offline  
Sponsored Links
Advertisement
 
post #2 of 8 (permalink) Old 03-22-2012, 06:55 PM
Planted Tank Guru
 
PTrader: (0/0%)
Join Date: Jan 2010
Location: Contra Costa CA
Posts: 11,721
Low pH:

1) If the KH is really low, then the pH can vary a lot. It used to be thought that the KH needed to be about 3 German degrees of hardness to buffer the pH, but many people are reporting stable conditions with just 1 or 2 degrees KH.

2) Unstable pH does not seem to be a problem for fish when it follows a day/night sort of cycle because of CO2. (Plants use up the CO2 in the day, pH rises. More CO2 enters the tank at night, pH drops)

3) If the pH is variable because of something else, then it is probably the 'something else' that is causing problems for the fish. Such as suddenly changing mineral levels with water changes. When doing water changes match the GH, KH and TDS. Do not worry about the pH. For Rams, I would filter the new water through peat moss. (mine bred several years ago, so I think I was doing something right)

4) Low pH (under 7.0) usually means that any ammonia is present in the ammonium form, and is less toxic to the fish. Plants can use either form.

5) pH under 6.5 is very difficult for the N-cycle bacteria. They thrive with the mineral levels usually associated with a pH in the mid 7s, and can handle pH 6.5 to 8 pretty well. At pH 5, I see serious problems with the bacteria part of the bio filter. This need not be a problem in a planted tank.

6) I am not sure which forms of algae are favored at that pH, but I am sure some form is adapted to thrive under those conditions.

How I would handle this:
Check that the GH and KH suit the fish. Ignore the pH unless you find there are some problems that you think need to be addressed. If you want to raise the pH, you can add some carbonate or bicarbonate (baking soda is one source) to raise the KH, and this will raise the pH.
Dosing: 1 teaspoon baking soda added to a standard 29 gallon tank with a canister filter (assume 30 gallons) raised the KH from 0 to 2 degrees. The pH in this tank tested at the bottom of the scale (6.0) and came up to 6.2.
If you want to use another form of carbonates I am sure there are recipes on line. Some forms may also raise the GH (Calcium carbonate) or might be hard to dissolve. I have not used these.
Diana is offline  
post #3 of 8 (permalink) Old 03-22-2012, 07:07 PM
Planted Tank Guru
 
GeToChKn's Avatar
 
PTrader: (1/100%)
Join Date: Apr 2011
Location: Hamilton, Ontario, Canada
Posts: 5,116
Low pH from CO2 is different than a low pH water. Whatever your pH is at with no CO2 at or from the tap or RO or whatever you use, that is your pH. If you have driftwood, leaves, etc in the tank leaking tannins, then that affects the true pH but a low pH induced my CO2 isn't your real pH.

Water pH is actually very complicated. That's why if you get RO water from any RO unit in your town, it's going to be roughly the same pH of the RO as your tap. Even though the RO may measure 0TDS, and been run through 7 different filters, there is still things in the water that affect the pH. Users on here that live in area's that have a pH of 8.6, get/make RO water that ends up at like 8 still.

20g platy, , 2 x 10g shrimp, 3 x 20g shrimp, 7.5g shrimp and 1 great dane/mastiff puppy.

Sump Pimp #2


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
GeToChKn is offline  
 
post #4 of 8 (permalink) Old 03-22-2012, 07:17 PM
Planted Tank Guru
 
PTrader: (0/0%)
Join Date: Jan 2010
Location: Contra Costa CA
Posts: 11,721
Quote:
Users on here that live in area's that have a pH of 8.6, get/make RO water that ends up at like 8 still.
Well, not always.
My tap water pH is in the mid 7s to low 8s (varies through the year). The water company adds sodium hydroxide to the water to raise the pH. KH is almost always 4-5 degrees year round.
When I had an RO unit the pH came out pretty close to neutral, or slightly acidic, even when the unit was getting old, and starting to allow some stuff to pass through. It still removed the minerals and other things that altered the pH. I had no test for sodium hydroxide (except seeing what the pH was doing) but the KH test showed 0 degrees. The pH was very easy to change; I added peat moss to this water for some pretty nice black water, and the pH dropped to 6-6.2 in just a few hours.
Diana is offline  
post #5 of 8 (permalink) Old 03-22-2012, 11:59 PM Thread Starter
Planted Member
 
PTrader: (0/0%)
Join Date: Jul 2011
Location: Portland, OR
Posts: 161
well, at the moment my CO2 is on all the time, so maybe getting a timer and only having it on during the day would help the PH come up a bit. Our tap water here is 0GH, 0KH so not sure if it'd be worth it to dose baking soda when I do water changes.

it looks like GBR's like hardness of 2-5 so that's not all that hard, hopefully that means they'd be good with really soft...

I guess my main concern would be over not being able to have the proper bacteria in my filter. What should I look out for which would be an indication of problems arising? would it just mean that there's more fluctuation when I do water changes?
U2Kent is offline  
post #6 of 8 (permalink) Old 03-23-2012, 01:04 PM
Planted Tank Enthusiast
 
PTrader: (2/100%)
Join Date: Nov 2011
Posts: 828
Your fish are alive, don't mess with it. That's the hardest part of this hobby.
fusiongt is offline  
post #7 of 8 (permalink) Old 03-23-2012, 05:58 PM Thread Starter
Planted Member
 
PTrader: (0/0%)
Join Date: Jul 2011
Location: Portland, OR
Posts: 161
Quote:
Originally Posted by fusiongt View Post
Your fish are alive, don't mess with it. That's the hardest part of this hobby.
this is true... yeah, guess I'll just keep doing as I'm doing and hope that not having a buffer doesn't bite me in the butt.
U2Kent is offline  
post #8 of 8 (permalink) Old 03-23-2012, 06:07 PM
Wannabe Guru
 
Higher Thinking's Avatar
 
PTrader: (23/100%)
Join Date: Mar 2011
Location: Oregon State Beavers!
Posts: 1,533
GBR's come from soft, acidic water. If I'm not mistaken they come from water that is like 5.2 typically. I am curious as to what the other user mentioned about "water" pH being different from pH from co2. A co2 probe doesn't know whether I used co2 to reduce it or not yet the pH controller obviously adjusts as I add more gas.

I can't help but feel that person is incorrect. PH is pH, no matter how it is achieved. The pH coming out of the tap is not your "real" pH. That is why when you are testing your tap pH, you are suppose to let it sit for a day or so. Know why you do that? Because it off gases co2 and the pH rises accordingly. So yea, you're actually pH is definitely dependent on co2.
Higher Thinking is offline  
Reply

Tags
None

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome