# PH Profiling - how do I do it?



## aaron.c (3 Feb 2015)

Hey Guys

I have a major BBA problem at the moment.

I have changed a lot of stuff recently to try and alleviate this. I have added an inline diffuser, and a spray bar, as well as reducing lighting intensity.

I want to conduct a PH profile to see if my work has been effective at sorting the CO2 stability.

I have seen PH profiling mentioned a few times and wanted to get some facts on how to do it.

From what I have seen, you do the following;

Test PH before Co2 comes on.
Test PH every hour (or more frequently) between lights on and when lights go off.
We are aiming for a drop of 1 PH unit before lights come on.

Where do we need to sample the water from? I could use a pippette to get water from various levels in the tank, but should I?

Thanks for any feedback
Aaron


----------



## ian_m (3 Feb 2015)

Yes to all. Just try to be consistent where you get your water sample from. Try with water samples at bottom of tank.

At a first pass, just dunk pH probe in top of tank, if not getting 1 drop of one, no point taking water from elsewhere until this is sorted.

The graph here shows the ppm CO2 for pH and water hardness. You will see for most dKH values 1pH drop gives about 30ppm CO2.
http://tropica.com/en/guide/make-your-aquarium-a-success/fertiliser-and-co2/

Generally, due to other salts & acids & bases in your tank water, the CO2 level will be under read, so pH drop of one equating to 30ppm needs to be taken with a pinch of salt.

I found that placing a drop check in certain places of the tank, before I got better CO2 distribution it was yellow in some places and blue/green in others. The blue/green drop checker areas suffered algae....


----------



## aaron.c (3 Feb 2015)

Thanks Ian!

I will let you know how I get on 

Aaron


----------



## Paulo Soares (3 Feb 2015)

Regarding also that you might not be able to drop 1 ppm cause of KH. 
No matter how much Co2 you inject.. so pay atenttion to fish. 

KH works as a security valve. 
Unless you drop fisrt you hardness (if needed) you might not be able to achieve a 1 PPm drop. 

My case..


----------



## Paulo Soares (3 Feb 2015)

i dont´ understand that Tropica table... 

I used to measure by this one:






For instance i used to have a 7.6 PH and a 10 KH. But no matter what i never riched a drop till 6.6 no matter how much i injected. I always get to a point where fish started to be at the top of the water..
So be regardless in that drop. 

It´s just this what i mean to say.


----------



## aaron.c (3 Feb 2015)

Thanks Paulo

I had seen the issue with KH mentioned. I have ordered a KH/DH test kit, so I at least know what I am dealing with

Thanks
Aaron


----------



## Paulo Soares (3 Feb 2015)

Caution with the brand of the tests. 
I have this ones: Nutrafin, JBL, Amtra, Elos, Sera and Api. Testing for a long time now...most of tests are useless concerning their reliability Duration, colour tables amd other matters.

In my experience the best choice to have at home:

NO3 - Elos
PO4 - Amtra and Elos
PH -  JBL
KH - Amtra and Jbl. 
GH - JBL and Amtra.

Compliments


----------



## ian_m (3 Feb 2015)

Be careful about putting too much emphasis in the numbers (and using a pH controller...why ?) and getting them exact. Whilst your are pondering and calculating and testing and measuring to the N'th degree you will be not noticing you are farming algae and all the plants are all dying..

My advice is green drop checker everywhere in the tank and no algae, beats measuring and testing every time.


----------



## Paulo Soares (3 Feb 2015)

ian_m said:


> beats measuring and testing every time.



Just like i did since i increase the flow  each day i put the drop in a diferent place and turns yellow in each.


----------



## aaron.c (3 Feb 2015)

I have ordered some extra drop checkers, so I can measure different spots in the tank too.


----------



## tug (4 Feb 2015)

aaron.c said:


> From what I have seen, you do the following;
> 
> Test PH before Co2 comes on….


You want to be sure all of the CO2 in your sample has reached ambient CO2 levels of about 2-3ppm by letting a sample sit for a day. Then a drop in pH of 1-1.2 degrees, irregardless of KH, corresponds to 30ppm CO2.

My personal experience with this method made me realize how little CO2 I was keeping. The problem Paulo mentions having with fish at these levels are more likely due to maintaining good gas exchange at the water surface and O2 levels.


----------



## pepedopolous (4 Feb 2015)

Is there any consensus on how we measure the pH drop?


By measuring the initial pH in the aquarium itself.
By measuring a water sample that has been left to stand?

My results: -
pH in aquarium before CO2 injection = 6.92
stable pH during CO2 injection = 5.65 (difference = 1.27)

pH of aquarium water left to stand for days = 7.58 (difference = 1.93)

KH = 4


Cheers,

P


----------



## tug (4 Feb 2015)

I can not be 100% sure that someone else's tank is gassing off all of it's CO2 an hour or two after CO2 and lights are out. Mine does and in the morning, before the CO2 comes on I can use it to check for pH. Your water sample would suggest that your tank does not (work on that) meaning, you should use a water sample until you do. If not you may have more CO2 then you thought. This may also explain what happened to Paulo.


----------



## tug (4 Feb 2015)

tug said:


> more likely due to maintaining good gas exchange at the water surface and O2 levels.


Maintain good gas exchange at the water surface and O2 levels is what I meant, i.e., not doing these things causes fish stress,
especially when CO2 levels are higher.


tug said:


> use a water sample until you do.


 A water sample that reached ambient CO2 levels outside the tank.


----------



## tug (5 Feb 2015)

It even explains why pH meters that shut down CO2 might be off, when can filters are used. Ian briefly touches on this on his post.


ian_m said:


> Be careful about putting too much emphasis in the numbers (and using a pH controller...why ?) and getting them exact. Whilst your are pondering and calculating and testing and measuring to the N'th degree you will be not noticing you are farming algae and all the plants are all dying...


Paulo, you just like anything ian-m posts.


----------



## tug (5 Feb 2015)

In most cases were BBA and CO2 are concerned, most of the problems I've had, abated when the added CO2 and CO2 lost, find a balance. This maters more to me then what level it's at. I do not think preventing BBA takes more or less then 30ppm CO2. The plants determine what level of CO2, light, etc., you need. CO2 levels can be maintained at any level, as long as in = out. Best kept over 9ppm, if you're going through all this effort but with a stable 20-25ppm CO2, under 30-40mmol PAR, if your dosing properly, BBA has a hard time keeping a foothold. If it does hang on, 30-45ppm will stop it under damn near any PAR we keep over a planted tank. The need for CO2 in PAR around 60-80mmol, is still a stability issue - In=out.


----------



## tug (5 Feb 2015)

pepedopolous said:


> My results: -
> pH in aquarium before CO2 injection = 6.92
> stable pH during CO2 injection = 5.65 (difference = 1.27)
> pH of aquarium water left to stand for days = 7.58 (difference = 1.93)


A difference in the drop in pH of 0.7 due to CO2, is around 10 to the .7 power, or about a factor of 5, if I understand the math correctly. Assuming the acclimated water had 3 ppm, you might have about 15 ppm of CO2 in the tank before the CO2 even comes on.


----------



## pepedopolous (5 Feb 2015)

Hi Tug,

Thanks for your help, good food for thought. Unfortunately, I nearly gassed all my livestock today thanks to an 'end-of-tank dump'. I've never had this before but it's a new regulator so I need to see what the supplier says about this.

P


----------



## Dan-CR4 (5 Feb 2015)

pepedopolous said:


> I've never had this before but it's a new regulator


What Regulator was you using, have you a link?


----------



## pepedopolous (6 Feb 2015)

I'm sure I read here that it EOTD shouldn't happen with quality single stage regulators.

My old Lunapets regulator never had an EOTD. This company is now defunct but I bought this one instead: -
http://www.us-aquaristikshop.com/co...abschaltung-inline-mit-rueckschlagventil.html

The regulator (manufactured by Hiwi http://www.biertrinken.info/produkt-0109.9drossel.html), is also sold by several German companies such as UKAPS-sponsors Aquasabi, and is also re-branded by Sera 

(https://www.sera.de/en/products/in_.../product/sera-flore-co2-pressure-reducer.html) 

and Tunze
 (http://www.tunze.com/149.html?&L=1&C=SE&user_tunzeprod_pi1[predid]=-infoxunter031)

Anyway, with the help of my German-speaking girlfriend, we'll see what the supplier says about this...

P


----------



## Andy Thurston (7 Feb 2015)

Some people use cheap single stage regs and never have a problem with eotd. Eotd can happen with any single stage reg so for complete peace of mind the use of dual stage regs will prevent this happening. Just because someone says it doesn't happen doesn't mean it wont


----------



## pepedopolous (7 Feb 2015)

As far as I'm concerned EOTD = regulator not fit for purpose.

P


----------



## Andy Thurston (7 Feb 2015)

pepedopolous said:


> As far as I'm concerned EOTD = regulator not fit for purpose.
> 
> P


Me too


----------



## Christos Ioannou (23 Feb 2015)

tug said:


> I can not be 100% sure that someone else's tank is gassing off all of it's CO2 an hour or two after CO2 and lights are out. Mine does and in the morning, before the CO2 comes on I can use it to check for pH. Your water sample would suggest that your tank does not (work on that) meaning, you should use a water sample until you do. If not you may have more CO2 then you thought. This may also explain what happened to Paulo.


Hi Tug,
In water left to stnd for 2 days, taken from the tank, I get pH 7.8

In water from same tank, just before co2 is on, I get pH 7

1. Should I ve aiming for pH = 6.8 OR 6 at lights on time? 
2. Should I aim in better gas exchange when co2 is off to get my pH in tank same as that of the water left to stand?

Thanks.


----------

