Low PH

[wuldiba]

I have been battling with low ph in my 25g reef tank for a couple of months now, it is always around 7.8 to 7.9, and I have been buffering relentlessly to try and get it up. It goes up for a day and by the next morning its back to 7.8 again. Thing is my water for water changing I usually leave to mix for about a day but and I always test before putting into tank, on this occasion it has been sitting in my clean bucket for 2 days with a hob waterfall type pump that i use to circlate the water and i decided to test the ph of this and it too was 7.8 ???????? IN FRESH CHANGE WATER????

dont think its a co2/oxygen thing as its physically impossible to agitate the surface anymore and my bucket is sat next to a drafty door to the outside?

any suggestions welcome as I'm pulling my hair out!

parameters in tank are

cal 550

mag 1350

kh 13

ph 7.85

 

oh, and I use reef crystals

[Mr. Fosi]

Bad kit?

[wuldiba]

Bad kit?

maybe, but im using a ph meter that gives me good readings in my fw tanganyikan tank (8.3)?

[SeeDemTails]

Good question.....PH is pretty hard to get wrong.

 

Do you have a skimmer? Are you surface skimming you tank, or does it have a scum layer on the waters surface? This will severly impeed gas exchange, thats why surface skimming is so important.

 

PH buffers are never a good thing to add to the tank that often, you might throw your ca/alk balance out of whack.

[The Propagator]

Do you smoke in your home excessively ?

Is your tank covered?

Is your home well ventilated?

 

Aside from doing these 4 things:

using a calcium reactor with to much co2 injection.

using cheap low quality salt on top of using low ph R/O water ( some times adjusting the ph of your pure R/O water is needed).

Dosing to much baking soda to buffer your alkalinity.

Using the wrong kind of DIY rock or some other wrong kind of natural rock.

 

About the only way you can repeatedly have low PH is if you have excessive CO2 build up either in your home or in the water column from lack of ventilation or gaseous exchange.

 

If its a covered tank remove the cover and let it breathe.

[wuldiba]

Thanks for the replies people, I think the general consensus is that its a gas exchange/co2 problem, however what threw me is the ph drop in my fresh water change in an open bucket that only sat for 2 days? This bucket is open, next to the outside door which is open quite a lot of the day, has a pump which really blasts the water and its surface and obviously has no rock or fish or any type or organics to pull the ph down. Think I'll change my salt today and do some tests with some water, ill keep some outside for a while and see if it makes a difference.

In my tank it is open top, only has a skimmer running through night time (11pm till 8am), and in tank I have the output from a 1200 lt external on a hydor rotator, 1 x maxijet 800lph and 2 koralias, one of which I have pointed at the surface, I couldnt get any more in to a 25g tank !!!!!!!!

[wuldiba]

Heres a pic of the tank, Go easy, its only 3 months old, but you can see the skimmer, deflector(1200lph) and kor on the left, and an other kor on the right with an intake,,,,,,,

[wuldiba]

Did an airation test with a glass of tank water;

tank water ph was 7.93

outside air after 1 hour was 8.19

inside air after 1 hour was 8.07

 

not a big difference between inside and tank, but a big difference from tank and outside.......

what to do???? open up the windows?

and am I making the right summising here?

[Mr. Fosi]

Looks like you need some fresh (less CO2) air in the room with your tank..

[The Propagator]

Open that biatch up and air it out.

Check out your attic ventilation, check your gas range, check your furnace.

[MrAnderson]

Did an airation test with a glass of tank water;

tank water ph was 7.93

outside air after 1 hour was 8.19

inside air after 1 hour was 8.07

 

not a big difference between inside and tank, but a big difference from tank and outside.......

what to do???? open up the windows?

and am I making the right summising here?

 

excellent work. i wish more people did stuff like this so they could see for themselves the effect of indoor CO2 instead of just dismissing it out of hand.

 

+10 NR points scored.

 

oh, and you know what works really well to correct this? some macroalgae in the display, photosynthesis consumes CO2. pick out something pretty.

[The Propagator]

But be very selective. Most of the pretty macro takes over every thing.

[eklikewhoa]

Off topic but what kind of Tanganyikans do you keep?

[The Propagator]

My guess ... the Cichlid kind. OOOOOHH !!!! I'm on a roll, !

[eklikewhoa]

Well did you know there are Tanganyikan catfish/puffers/crabs/killie fish/etc........?

 

Single roll of a six sided dice my friend.

[The Propagator]

A roll is a roll....

[wuldiba]

Off topic but what kind of Tanganyikans do you keep?

yeah, I've got a mixed community in a 150g,

 

I have a breeding harem of ten leptosoma kitumba, 2 yellow calvus, 1 brichardi, 2 Juliochromis transcriptus,

3 leilupi, 1 synodontis multipunctus and probably over 30 multifasciatus with there shells.

 

ive also kept a lot of american cichlids that I used to post pics on my blog http://www.williamdalling.pwp.blueyonder.c.../new_page_6.htm ............Im a bit of a cichlid fanatic