Urgent Chemistry Question!!

[Geoff]

i have no idea what is wrong with my system. no matter what i add to the tank the pH drops like a stone. i mean literally. when i left this morning it was at 6!!

my alk is at 5 because i have been trying to rais the pH. when this all started it was at 3meg/L. the rest of the usually suspects look fine. mg is 1250, Ca is at 400.

i am completely clueless. i hope everything survives, but am expecting the worst. when i get home today i will do a near 100% water change unless some idea as to what is going on is found.

i have recalibrated the pH probe. i have put it in several different solutions and it hits it. not that.

whenver the kalkreactor tops off the pH will drop then slowly go up. i am talking less than a couple of ounses of fluid here for a near 200g system. the kalkwatar test out at 12. i have tried sodium bicarbonate, both straight and the cooked variety, both cause the same phenomena.

Nikki is stumped also. everything we try to raise the pH backfires. last night i put in about 8oz of kalk water into the sump the pH jumped to 7 then by morning it was back down to 6!!!

needless to say i have calcium carbonate all over the place. the critters are still holding in there, but i do not know how long.

more info. my diy chiller died, it is completely closed to the aquarium and i can guarantee that chiller water is not mixing with aquarium water. could there now be bacteria in the warmer chiller coils that could be supplying CO2 into the system to drop the pH? everything i have read tells me that CO2 is the reason why a reef tank would have a low pH.

ARRRGGGHH!

thanks,

G~

[yardboy]

Have you isolated the chiller from the system? I can't imagine I could contribute anything your wife hasn't (phD in chemistry?) but I swear I'd look at the pH probe first. Probes have an evil way of calibrating fine with buffer and then not behaving when you put them in the sample(different ionic strengths). Is the calcium carbonate fallling out of solution? If the pH is really 6, I'd think fish and corals would be climbing out of the tank.
Sorry I can't be of any more help than that.
Doe you have a calcium reactor? If so, might ought to shut off the CO2 supply and see if that helps.

[512148048]

is there a ton of cayno? because cayno is feeding on po4 but aPh drop occurs fast then they will just go nuts.

[Geoff]

good questions.

i do not have a Ca reactor only a kalk reactor.

i took a glass from Nikki's system and put the probe in it and it was 8.0. Nikki will bring home so dip strips to see if it is some kind of ion problem.

i totally agree that the critters would be really reacting badly if it was that low. they just seem mildly PO'd. the clams were as open as normal for before lights on. the acros had their polyps out also. a couple were sliming, but not real bad.

at this point i am really hoping that the pH is really 8.6 now that i have wigged with so much buffers and the pH probe is not reading it right for some reason.

i have issolated the chiller from the system, and it not seem to have an effect. the problem was it was at night so it does not run much. i should try that when i get home. i can put the probe down the chiller return and see what happens.

G~

[Geoff]

Originally posted by 512148048
is there a ton of cayno? because cayno is feeding on po4 but aPh drop occurs fast then they will just go nuts.

very, very little.

G~

[Geoff]

bump.

G~

[tdwyatt]

Sorry Geoff, I will call now for more info.

[Geoff]

i will not be home until about 6:30. i have to go get some salt.

thanks,

G~

[Kevin1000]

Heres a link that will help.

http://www.advancedaquarist.com/issu...e2002/chem.htm

[btang]

This sounds like a situation I read about in a book titled 'Live Sand Secrets' by Bob Goemans. He talks about trying to control the PH by adding Kalk but it doesnt work. Have you check your Magnesium levels. Quote from book ' remove enough magnesium from your system and your PH will always be drivng towards 7.6'. Just a shot. Good Luck.

[512148048]

hope it don't hurt any thing you have a very cool tank

[shawn]

more info. my diy chiller died, it is completely closed to the aquarium and i can guarantee that chiller water is not mixing with aquarium water. could there now be bacteria in the warmer chiller coils that could be supplying CO2 into the system to drop the pH?

Geoff-
How is your chiller isolated, and more importantly, how did it die? Not sure how it would affect pH, but I can guess, as refrigerants are made up of cfc's... if it were leaking into the water supply... . Its a far shot, as the design of these is supposed to prevent this, but I have seen worse things(I'm a refrigeration tech. ) and it is possible. If all thats holding it back are a pvc ball valve, it is possible for it to still leak by. Just something to consider...

Shawn

[yardboy]

He has a DIY chiller that is basically a bucket of water sitting in a refrigerator with a plastic hose looped through the bucket. Not much chance of comingling of fluids, but you never know.

By the way, Geoff, do you add vinegar to your kalkwasser? Possible you added too much or double dosed or something?

[shawn]

sorry...I was thinking of an actual chiller....

[Geoff]

thanks you all, Tom and i banged on it for a while last night. i have made up 140+ gallons of water for a water change that i will do when i get home.

are you all ready for this!

the pH probe is acting funny. the pH in the tank is actually fine. it is a little low now due to the fact that the lights were off. the water however is still ionically wiggy.

the water change is still necessary, but the critters are all fine.

i will start another thread about the pH probe because this is still very weird.

G~