Dramatic pH drop...tanks not well...any advice please?

[reefcoral]

:frown:

Hi all,

Came down this morning and pH was 7.15!!!!!! Any emergancy advice on what I can do please?

I have new water ready to put in shortly, but I seem to have an underlying pH problem.

I mentioned in a thread last night to George that the tank suffered from low pH 7.7 to 7.8 by day and 7.5 ish by night. However, as the tank inhabitants seemed quite stable and healthy I was not too concerned.

But this morning shrimps look as if they are not going to make it and corals looking decidedly off colour.

Setup is as follows:

Tank has been setup 14 months
300 litres
1 inch coral sand (mainly fine but also about half a litre of larger crushed pieces)
40Kg Live rock
Salifert Red Sea Coral Pro salt
SG 1.027
Temp 25.5
calcium 420
Mag 1500
Nitrate<20ppm
phosphate 0
nitrite 0
amonia 0
UV sterilizer
Rowaphos
carbon
koralin denitrator
Koralia 4 and MPw40 Vortech

Test kits are all Salifert with a PinPoint pH monitor which is dual calibrated with PinPoint fluid.

Has the buffering capability of my sand run out? Should I replace it slowly?

Cheers,

Dave

[Gaters]

I would point a powerhead at the surface and maybe put an airline bubbling into the tank to help with gas exchange. I would say your salinity is around 38 (using the free table) which is a touch high also. I'm no expert though.

[Tangman]

Hi Dave all your params look good except for the SG at 1027 it is a bit high needs to be around 1024/5. Also do you have surface movement on the water ie powerhead pointing at the surface to aggitate it, as this will make the PH more stable also opening a window and letting fresh air in also helps.Have you tested a salted water mix for PH etc before adding to the tank, this may bring something up why it is low. Replacing the sand wont make much difference so leave it as it is. HTH Twiggy:D:D

[Timo]

Your PH will always fall to a more neutral 7.7 unless you are buffing. Sand is so hard it wont really buff your PH up at all. As Gaters said adding more flow helps. Also is the tank open top? A fudge will also help keep the PH high. You can use a calcium reactor or ball method also.

[mikk1301]

is the de-nitrator a sulphur one? is the out put of this buffered at all this will drag the ph down.regards mikk

[reefcoral]

Thanks for the responses guys.

I have also popped an airline in there this morning. The pH is now up to 7.60 and one of the shrimps has gone:frown:

The tank is open topped and I have a Koralia 4 to create the surface aggitation.

The denitrator is a sulpher bead one and it does have a buffered output. Got it off of Mazza the other day. I have no refugium, but I'm planning on adding a 2 part sump when I move up North and I can drill the back of the tankwhen it's empty.

Before I add the new water I do test it with the Pinpoint monitor and it is always ok. However, I don't tend to buffer the water with additives, but I do have some Salifert Kh and pH buffer which I have added today under the circumstances.

I will start to lower the SG on your advice when I do the water change today.

I see George has a calcium reactor going so I'll put in for it and see if this will help in the long term.

Cheers, any other thoughts??

Dave

[cav]

Are you using a ph monitor? If so when did you last calibrate it?

[reefcoral]

Hi Cav,

I'm using a Pinpoint pH monitor which was calibrated last about 5 weeks ago and had a new battery last week. The visible signs in the tank this morning showed something was definately very wrong.

I'm asking George if a Calcium reactor would help to raise and stablize my pH. Have you any thoughts on this?

Dave

[reefcoral]

Just thought I'd let you know everything seems to have settled down now. Unfortunately lost a shrimp, but luckily that was all. The Corals have sprung back to life and the pH is now at 7.80. Clearly still on the low side and I'm lost to know what to do. I don't want to keep throwing in Buffer and then create another problem with some other aspect of the chemistry. I am still slowly lowering the salinity to 1.024/5 as suggested, I have an airline running and have been busy cleaning up all the kit. I'm going to re-calibrate the pH monitor, but irrespective of any inaccuracy the signs of stress were quite visible in the tank.

Thanks for the help and advice.
Dave

[ridley322]

Hi in regards to salinity i have droped mine from 1.025 to 1.022 after visiting a frag sales man whos frags were stunning and thriving. not only does it cost less in salt water but i can now keep pulsing xenia which i could not do before

[angel1]

do you have good ventilation in your room ??

interesting that bit about pulse, i know mikes never been able to keep the stuff, even though his regal tang takes bites of it the stuff never does well anyway, he keeps his tank around 1.027 as well

LILYANN:p