PH fluctuating

youssefrf · Feb 23, 2017

Hi

I started setting up a reef tank 20 days ago and in the middle of cycling the tank right now.
I am using pure ammonia for Fish-less cycling
parameters:
NH4 approx. 0
NO2 7
NO3 40
Calcium 360
KH 6.5 dkh

my problem is PH; it keeps dropping from 7.8 to 7.4 in 24 hours.
I started adding Kalkwasser to my top-off RO water; PH then goes up again to 7.8 but not more and then goes back again to drop drastically to 7.4 or 7.3 till the next top-off.

how to get PH to 8.2 and how to prevent it from this fluctuation.
is it going to affect fish and invertebrates once added to tank if the problem continued?

thank you for your help

sonubhai · Feb 23, 2017

Hello, if your tank is cycling there is no need for you to add kalk. Your ALK is low too. IMO I would not worry about the parameters much while your tank is cycling.

youssefrf · Feb 23, 2017

thank you. so you recommend to wait till cycle finish then decide what to do

sonubhai · Feb 23, 2017

I would say so, try opening up windows to the room the tank is in that should help with the ph levels. Once the cycle is complete then i would worry about ph levels. The can easily be corrected by slowing adding various ph buffers, that are available in the market. What kind of salt you use? your alk is kind of low too.

youssefrf · Feb 23, 2017

i used ready sea water treated for bacteria and other stuff
do yo recommend to use salt mixed with RO water instead

sonubhai · Feb 23, 2017

People successfully use treated sea water for reef keeping without any issue. If the source you are getting from is trusted it shouldn't be a problem. People also use synthetic salt and RO water so they have more uniform levels of elements. I personally use RO water and RED Sea salt since i dont have access to treated sea water.

saltyfilmfolks · Feb 23, 2017

Currently there is nothing in the tank to change the Ph. Its the animals(all, inc bacteria fish coral) breathing that effects your Ph on a daily swing.
Double check your salinity as well. for an empty tank using Kalkwasser its odd that the Alk and cal are so low. They should be closer to the salt's parameters.

saltyfilmfolks · Feb 23, 2017

youssefrf said:
Hi

I started setting up a reef tank 20 days ago and in the middle of cycling the tank right now.
I am using pure ammonia for Fish-less cycling
parameters:
NH4 approx. 0
NO2 7
NO3 40
Calcium 360
KH 6.5 dkh

my problem is PH; it keeps dropping from 7.8 to 7.4 in 24 hours.
I started adding Kalkwasser to my top-off RO water; PH then goes up again to 7.8 but not more and then goes back again to drop drastically to 7.4 or 7.3 till the next top-off.

how to get PH to 8.2 and how to prevent it from this fluctuation.
is it going to affect fish and invertebrates once added to tank if the problem continued?

thank you for your help

And welcome to Reef2Reef!

Some of these articles are bit advanced, but there's several very good ones for newer Aquarists.
https://www.reef2reef.com/threads/randys-reef-chemistry-articles.174821/

beaslbob · Feb 23, 2017

Welcome

IMHO your pH is low because you're using ammonia and still cycling. But even more important is the co2 is not being consumed. If you would add macro algae the pH would rise to the desired 8.2. And be sure to measure pH just before lights out. Ph will rise with lights on as the algae consumes co2 and then drop under lights out. What is important is the tank become a net consumer of co2 and source of oxygen each 24 hour period.

my .02

youssefrf · Feb 26, 2017

thank you all for your support.
good news. PH stabilized at 8.1-8.2 after taking your advice and opened windows.

now I have to see why ALK is low and how to raise it

thank you gain for your help

sonubhai · Feb 26, 2017

I wouldn't worry about elements while your tank is cycling. Once the tank is cycled and you are ready to add corals then I would worry about the elements. But most likely your problem is going to get resolved if you start using good quality synthetic salt with RODI WATER.

beaslbob · Feb 28, 2017

youssefrf said:
thank you all for your support.
good news. PH stabilized at 8.1-8.2 after taking your advice and opened windows.

now I have to see why ALK is low and how to raise it

thank you gain for your help

sounds good.

you can raise kdh with baking soda.

While you're at it look up and read Dr Randy Homes-Farley's improved diy two part system. It keeps calcium, alk, and magnesium in line using inexpensive dosing materials.

see: http://reefkeeping.com/issues/2006-02/rhf/index.php (from the sticky at the top of the forum)

skim · Mar 1, 2017

You will want bring those numbers up some and be stable, so as you are getting closer to the end of Cycling you want to bring your Cal and Alk up so you may want look at Salt and RO/DI in the future. I would not ad Kalk right now.