Ph KH C02

[Ob1]

I now have a pressurised C02 system. I need some advise can anyone help?

Firstly can anyone recommend a good quality Ph tester kit – I am currently using Nutrafins and I find it hard to make out the Ph reading once they reach 7.6 and above.

Secondly need some help with my reading and how to stabilise my Ph over 24hrs. Should I switch off the timer and keep the co2 on all the time – my ph swing seems large is it stressing my fish?

My tank parameters prior to the introduction of C02:

Ph 7.8
Kh 60
GH 120

In the morning they read

Ph 7.6

In the afternoon they read

Ph 7.4

In the evening they read

Ph 7.2

Middle of the night (3am)

Ph 7.6


I must admit my ability to obtain a good reading from the test kit diminishes throughout the day – (very difficult to read under house lighting).

I also have a solenoid attached to a timer, which controls the C02 – currently in line with lighting system approx 12hrs - Co2 set to 35bmp

All my fish seem fine – I am not overstocked – however I have introduced a number of new plants – 12 in total over the last 48hours

I am worrying unnecessarily? also finally my KH and GH are in mg/l what is the conversion factor to dh?


cheers

Ob1

 

[smithrc]

mg/l what is the conversion factor to dh?

phew - i thought it was high!

ppm × 0.056 = dH

so 3.36dH

That'll be what is causing the PH to swing. If you can, raise the KH to around 8dH and you'll be able to get 30ppm Co2 in there with the PH around 7.0

Co2 set to 35bmp

bmp?

I was guessing ppm - but to do that the system would have to be controled by the PH and it dosn't sould like it is.

bubble per minute? (bpm)

 

[Ob1]

Hi smithrc

Thank you for replying – most appreciated.

You are correct it should have read bubble per minute? (bpm)

How can I raise the Kh? And is it safe to do this? I had always been on the understanding that it was the Ph, which was either raised or lowered – by PH shifters and that these can be hard to control, any thought on that – or have I mis understood?

I have measured my Kh again, and it is now reading 30mg/l or 1.68dH – I had carried out a water change within the last 24 hrs but my tap water is still 60mg/l or 3.36dH. I was pumping around 50bmp should I reduce this – I do not know what’s happening to Kh my PH is currently at 7.4 – all the plants are pearling and the fish seem OK – apart from one of my blood fin tetras – he as gone a bit pale but seems OK.

I had assumed my reading of Kh (60mg/l) converted to 6dH and that a bmp of around 50 would lower the Ph to around 7 and increase the Co2 to around 18mg/l
Should I switch of the co2 until I better understand? I do not want to harm my fish.

Fyi It seems a lot of the plants I had in my tank required a dH of 5 and above L no wonder everything didn’t grow so well – the problem is I have just replanted the same types of plants all dH5 and above

any one

 

[smithrc]

Our main problem when we started out along the planted tank route, was the lighting.... we now ahave somewhere around 200W above our 50gal.

one way to raise your KH is to use baking soda. i've not doe it myself (as our KH is ok at 8deg) but its an easy method.

HTH.

(sorry for the brief reply - but i want to go to bed before father christmas comes )

 

[kenneth_kpe]

i add baking soda to my tank every so often to keep my KH at around 6 dkh nothing happened to my fish yet and ive been doing it for around 2 mo's now, but for other people 2 mo's is still a short time to be saying its okay

 

[Ob1]

I have now turned off the co2 system; a couple more of my fish went pale. I want my kH to return to its normal level of 3.36dH, ph at 7.6. I think my fish are showing signs of Ph stress.

I do not understand why my kH dropped so fast to 1dH - any ideas anyone?
And should I carry out a series of water changes over the next couple of days to help my water param?

I am going to consider raising the kH once I understand how and what to use also I feel leaving the reactor on 24*7 is better then switching off at night – what do you all think?


Cheers

Ob1

ps now have lots of hair algae

 

[smithrc]

I want my kH to return to its normal level of 3.36dH

Your KH wont have dropped....

Youe KH stays the same - your PH and CO2 levels change around your KH

So why it changed - I'm not sure...

I'd definatly start the bubble rate at lot lower and work up gradually - BUT only after raising the KH.

 

[Ob1]

thanks smithrc for sticking with this thread.

I have shut down the co2 completely until I can ensure I do not have any more large shifts on ph – I am sure my fish have been stressed at present I do not feel good about the whole thing – I really thought it would be straight forward. I have started to increase my knowledge of kh and it buffering capacity. I will look to raising the kh once I fully understand the implication.

This is a set back but luckily I have not lost any fish. It just goes to show how complex a material water really is, not something to be taken lightly…


thanks again ob1

 

[Ob1]

I have a couple of questions hope someone can enlighten me further? My currently tap water gives me a Kh of 3.36dH PH 7.6 –

I have read a lot of material; by rising my kH from 3.36 to 8 - I will actual raise my ph to 8, then by adding Co2 19mg/l, I will reduce the ph to 7.1 – I understand why this happens however surly this is the same as me leaving my dH at 3.36 (natural water supply) ph7.6 and adding co2 to 16.6mg/l which will drop the ph to 6.8.. The only reason I can see to increase my dh to above 3.36 is to insure the water ph matches my fish? Eitherway I will need to control the PH shift tightly i.e. PH controller. – I know the higher the kH the more co2 can be added without PH change. Have I missed something about the kH buffering capacity?

Lastly

Too stress regarding Ph shifts – I have been looking at Ph controllers – both the AM PH control and AM PH computer both seem to cost about the same £200+

Does anyone use either one and can they recommend them??

Cheers

Ob1

 

[smithrc]

Hi Ob.

Your doing exactly what i did - reading up is the best way

We still havent got it right yet but we're getting there.

We're still using DIY yeast mixes. but looking at a more controlable method

 

[reiverix]

Raise the KH with baking soda. It's safe and efficient if you don't raise your pH too fast. I wouldn't go above a 0.2 pH rise over a several hour period.

Check out this link for the amount to add. I think it's in US gallons so you'll have to convert if you need to.

http/dataguru.org/misc/aquarium/calKH.asp

 

[Ob1]

The penny has dropped: D

I want to share this insight and thank all the people who helped me get there.

When I first got into adding Co2 (10 days ago) I had a major problem with everyone telling my I needed to raise the kH. I mean the Ph/Kh/Co2 matrix tells me a Kh of 3.36 and a drop of ph to 6.8 will result in 18mg/l approx. so why increase the kH? After all by increasing the kH you also increase your ph. So introducing more ph shifts equals stressed fish L

I now see that by increasing the kH (which happens to be simple and safe if done in stages) I end up with a PH target value, which takes into account the fish. But what I missed and I think s more important - is I now know that my water will remain stable until my next water change which happens to be 10-14 days. Introducing Co2 and natural waste makes the water acidic over time. The Kh buffer protects the water from becoming increasing acidic a short period of time (10 days). Image not carrying out a water change for 50 days – with a kH of 3.36 my water Ph might crash before I could replenish the waters ability to maintain the target ph.

So I have now started the slow process of raising my kH from 3.36 to 8, which, will provide a target ph of 7.0 and provide stability until the next water change.

Also I have started to understand that turning Co2 off at night may actual create more of a ph shift which is something I want to limit. It seems there is an argument that suggests co2 will natural disperse throughout the night. But that is an argument for another thread in the future.

Cheers

Ob1

 

[Stryker]

The CO2 in my tank raises during the night. This is because plants take in some oxygen and release CO2 during the dark times.

 

[Riccardo1976]

Yes but what if my ph is already at 7 and have only 3 degrees kh.
Adding baking soda will raise my ph to 8+ with drastic consequences won't it.

Any advice would be appreciated. I have the same problem. I want to add CO2 but need to increas kh so that ph won't crash. But if i raise the kh before putting in the c02 the ph will go to 8+

 

[Stryker]

My tap water has a PH of around 7.5 and (around) 4d KH. When I had my salty GSPs I just buffered the water with crushed coral, I trusted my LFS's advice as they have the same water.

I must admit I never noticed any problems, fish were fine. Maybe I was lucky, maybe the coral did not have such an instant affect on the water.

Sorry, other than "I got away with it" I have no advice on that. Got a spare bucket or something? experiment.