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StarF
10/06/2011, 12:43 AM
Hey

Due to a isue with my skimmer, i have ben running with out a skimmer for a few days while i get a new one. This night the PH dropped to 7.34, this is low i know. How long would my sps be ok with this? So far there is no chance to them, but i know when things go bad it can go fast, and there will be at least a few days before i can get a new skimmer again.

and yes the ph is accurate, normal my range is around 7.90 to 8.20 night/day so sadley the 7.34 is not a measurement isue. Normal i have to have the air intake from outside, or else my ph get as low it is now, now due to there is no skimmer there is no air from the outside being added to the system.

So short.. should i rush out and get a new skimmer, or should the system be able to take it for a 2 days more? I am thinking when sps get shipped, the ph in the bags must get a bit low aswell ?

chrishayes
10/06/2011, 10:30 AM
Yeah, im sure things will be ok but you never know. Im no expert especially on the matter of chemistry and how ph truly effects coral but as you said during shipping and storage at various stops along the way im sure they see ph lower than what youre seeing. That doesnt mean it isnt harmful, especially in a mature setup that is used to stability. I know ive read studies that in the ocean when acidification causes ph to fall below 7.8 the diversity of coral species declines by a crazy sum and below only giant porites tolerate it. But, I think in the aquarium, there are a lot of us out here that have ph that stays around 7.8 even as a high so im not sure where that leads us.

That being said, can you add an air pump to your outside line and pump it into your sump/tank? Also, good ol waterchanges will help to raise ph along with handling some of the DOC's that arent being removed via your skimmer. I myself have ran plenty of tanks without skimmers but they were setup that way and as such werent dependant on one like the berlin systems most run anymore.

ReeferBill
10/06/2011, 10:40 AM
+1 on the water changes Keep doing small water changes until you get your new skimmer.:dance:

StarF
10/06/2011, 10:44 AM
the problem is, that even with water changes, my ph will fall that low. Its something with the air in the apparatment that i live in.

(btw i just did a 20%) water change... just as a test. 7.67 and slowly dropping.

stingythingy45
10/06/2011, 10:49 AM
What is your alk?

StarF
10/06/2011, 11:14 AM
alk is 8, ca is 470, mg is 1300ish...

its not my parameters, i always had this isue, even with my skimmer running my ph will run around 7,6-7,7, unless i take in fresh air from the outside, then its back at 7,9-8,2. i have never figured out why.

dzhuo
10/06/2011, 11:38 AM
pH of 7.3 is low (assuming it's not a measurement issue).

It has been shown to affect and stress fish (such as salmon). Lots of invertebrates (such as oysters) are also affect by its ability to form a hard shell and larva survival rate falls significantly. Corals are also affect by low pH at 7.3. Studies of growing corals in pH of 7.3 vs 7.6 reveals skeleton of hard corals are completely missing with pH at 7.3. Although the corals can continue to live (presumably due to strong internal pH control), they aren't unable to form a hard skeleton (see Scleractinian Coral Species Survive and Recover from Decalcification for more detail). Interestingly, when those corals are put back in normal marine environment, they regrow their hard skeleton so this appear to be no long term negative affect (base on this single study).

pH in salt water is purely a function of alk and CO2. Since you don't have a alk problem, water change will not help at all (pH will quickly fall back due to ambient CO2). The only option you have is drip kalk or find ways to reduce CO2 (such as growing macro). Using a air pump will not help either and likely to accelerate pH drop by introducing more CO2 to the tank.

I would suggest that you find a cheap skimmer locally just to pull fresh air in. Having said that, with pH at 7.3 for a few days might not have a long term negative affect.

dzhuo
10/06/2011, 11:40 AM
(btw i just did a 20%) water change... just as a test. 7.67 and slowly dropping.

Yup. Forget about water change or air pump. It will not help (and air pump will likely accelerate your pH drop). pH is purely a function of alk and CO2 and since you don't have a alk problem, it's ambient CO2 that dictate the tank's pH.

StarF
10/06/2011, 01:25 PM
pH of 7.3 is low (assuming it's not a measurement issue).

It has been shown to affect and stress fish (such as salmon). Lots of invertebrates (such as oysters) are also affect by its ability to form a hard shell and larva survival rate falls significantly. Corals are also affect by low pH at 7.3. Studies of growing corals in pH of 7.3 vs 7.6 reveals skeleton of hard corals are completely missing with pH at 7.3. Although the corals can continue to live (presumably due to strong internal pH control), they aren't unable to form a hard skeleton (see Scleractinian Coral Species Survive and Recover from Decalcification for more detail). Interestingly, when those corals are put back in normal marine environment, they regrow their hard skeleton so this appear to be no long term negative affect (base on this single study).

pH in salt water is purely a function of alk and CO2. Since you don't have a alk problem, water change will not help at all (pH will quickly fall back due to ambient CO2). The only option you have is drip kalk or find ways to reduce CO2 (such as growing macro). Using a air pump will not help either and likely to accelerate pH drop by introducing more CO2 to the tank.

I would suggest that you find a cheap skimmer locally just to pull fresh air in. Having said that, with pH at 7.3 for a few days might not have a long term negative affect.

tnx for a verry good response, i should get my new skimmer sometime next week, prob on monday, or thuesday so its only ben 4 to 5 days without. So far the corals dosent show any signs of stress, they even have their polyps out. THe smart thing to do, would seem to be dont do anything drastic that might caus stress, and wait it out for the next few days. again tnx.

chrishayes
10/06/2011, 02:06 PM
I was saying to hook the air pump to the line he has coming in for the skimmer so it would be pulling and pushing outside air the same as his skimmer would.

I also wasnt thinking that the waterchange water would be being made in the same environment as the tank. Duh

dzhuo
10/06/2011, 02:18 PM
I also wasnt thinking that the waterchange water would be being made in the same environment as the tank. Duh

Well, this would still not help because as soon as you pour the fresh water into the display, pH will start dropping again due to ambient CO2. If you have a CO2 problem, it's impossible to fix by water change (regardless how or where the water is prepared).

dzhuo
10/06/2011, 02:19 PM
THe smart thing to do, would seem to be dont do anything drastic that might caus stress, and wait it out for the next few days. again tnx.

I agree. However, I do feel dripping kalk is fairly safe so it's something worth looking into.

dzhuo
10/06/2011, 02:20 PM
I was saying to hook the air pump to the line he has coming in for the skimmer so it would be pulling and pushing outside air the same as his skimmer would.

This sounds like a fine plan. It will help assuming you are able to hook up a fairly powerful air pump to offset the ambient CO2. A standard (non pressure driven air pump) might not be enough but worth a try.

piusma
10/07/2011, 09:22 PM
How about a aqua lifter where you could run a long intake hose from the windows and bring fresh air in from outside your apartment into the tank? or may be open a window to let some co2 out for a few days? It's probably the waste in the water that is raising the ph so in theory doing water change will help. At least that will help with your nutrient level so you don't get any algae outbreak.

Steven

A. Grandis
10/08/2011, 01:16 AM
Skimmer shouldn't have a strong impact on the pH.
Normally the low pH is already about 7.8 or 7.9 for the marine aquarium.
Try to dose kalkwasser and buy a good skimmer, independently of the pH problem, because skimmer is very helpful in any salt water system anyway.
Grandis.

njreefermadness
10/10/2011, 10:22 AM
If you could agitate the water's surface, it may help blow off some CO2 and get more O2 in the water. If you could aim a powerhead towards the surface, or even bring it up so it draws in a little air, that might help the situation.

StarF
10/11/2011, 05:54 AM
a short update for those interested, still no sigh of a working skimmer, i guess it will arrive in the end of this week. The system runs atm around 7.4 og 7.6 in ph, i can tell you that i had to turn off my calc reactor, as there is little to no consumption in calk atm. corals has lost most color, some still have pe, but ALL color is dull.. they havent browned out or anything, blue,red, and so on are just dull and faded. 2 corals has had a little stn.

mabye i should take a picture so people can see the colors before and after, just for the fun off it.

SaltwaterAdict
10/11/2011, 06:27 AM
Pull fresh air in from outside via your skimmer or an airpump and will likely help out. Other than that you can keep up with waterchanges and add an alk additive.

power boat jim
10/12/2011, 08:42 AM
One other reason that drops pH is there may be decaying organics in the system. Are you running a deep sand bed by chance? If so hydrogen sulfide might be released into the system. If the sand bed smells of rotten eggs you found the problem. Unless your furnace or dryer is not venting properly that is an unusually low pH to sustain given all your perameters are within normal ranges.

Adding Kalk wont really do anything to keep the pH up long term, its not a buffer its a calcium suppliment. A true buffer would help but keep an eye on your alk if you use one.

dzhuo
10/12/2011, 09:28 AM
One other reason that drops pH is there may be decaying organics in the system.


Like I mention earlier, the only thing that matter to pH in salt water is alk and CO2. Nothing else. There is nothing that would change pH other than these 2 attribute. If I can't convince you, maybe Randy can:

PH ? New salt water (http://www.reefcentral.com/forums/showthread.php?t=1860860)

The pH of seawater is determined only by the alkalinity and the CO2 level.


Marine Salt lower pH levels? (http://www.reefcentral.com/forums/showthread.php?t=2001349)

There is no need to search further. pH of aerated seawater is ONLY determined by the alkalinity and the CO2 level.


Since OP has a stable and high enough alk, nothing else would raise pH except reduce CO2. Decaying organics would lower alk which would lower pH but if OP's alk isn't dropping then it's not the reason of lower pH.


Adding Kalk wont really do anything to keep the pH up long term, its not a buffer its a calcium suppliment.


That's completely false. Kalk is the only long term pH solution:

Chemistry And The Aquarium: Solutions To pH Problems (http://www.advancedaquarist.com/2002/6/chemistry)

The most useful method in this application is limewater. In this situation, the limewater is not being used to provide large amounts of calcium or alkalinity, but to soak up some of the excess CO2, and thereby raise the pH. The amount of limewater needed is not as large as for full maintenance of calcium and alkalinity. You can also put the limewater additions on a timer to add it only at night and early morning when the daily pH lows are most likely to be problematic. The limewater addition could also be on a pH controller, so that it is only added when the pH gets unusually low (such as below pH 7.8 or so).



A true buffer would help but keep an eye on your alk if you use one.

Kalk is the true buffer and everything else (such as the countless pH buffer on the market which does nothing but a temporarily alk spike) is pretty much useless:

ph buffer (http://www.reefcentral.com/forums/showthread.php?t=1352681)

Buffers are NEVER a good way to maintain pH, unless alkalinity is truly too low.

Do you have a low pH problem, or a low alkalinity problem?

If low pH, more aeration with fresh air, or using limewater are the best options.

dzhuo
10/12/2011, 09:33 AM
The system runs atm around 7.4 og 7.6 in ph, i can tell you that i had to turn off my calc reactor, as there is little to no consumption in calk atm. corals has lost most color, some still have pe, but ALL color is dull.. they havent browned out or anything, blue,red, and so on are just dull and faded. 2 corals has had a little stn.


Sorry about that. Maybe you should consider slowly raising alk to about 10 and keep it there with kalk. You would only need about 15% of kalk (saturate) to your tank vol to raise .3 unit of pH. This should help keep the pH around 7.7 which is a lot safer.

power boat jim
10/12/2011, 09:55 AM
DZHUO, you appear to have all the answers, I guess my years of experinces in this hobby, including having a hydrogen sulfide problem that did lower pH, could not have happened . I will stop here as I dont want to comment on anything that doesnt conform to your interpretation of quotes taken out of context from a different thread.

dzhuo
10/12/2011, 10:03 AM
Thanks for taking a cheap shot at me without providing any detail of how your years of experience in hobby matter so much more than a professional chemist and countless other hobbyists (myself included) also with years of experiences. Maybe you have redefined pH in saltwater and find a way to alter it without altering alk or CO2.

Whatever hydrogen sulfide problem you mention might have lower pH but it will also lower alk as well, period. If you don't have a alk problem and you are still having low pH issue, you have a CO2 problem. Feel free to search for a pH buffer.

If you think my quotes are out of context, feel free to take the discussion to the chemistry forum and I will be happy to continue the discussion but I will give you a hint: Everything I said in this thread will still apply in the chemistry forum. Btw, for all the quotes I took, I provide links to the entire discussion as well.

power boat jim
10/12/2011, 10:48 AM
OK, sometimes things can be read or understood online not as they are intended. To see you dismiss my experience in having the hydrogen sulfide problem as an alk or Co2 problem was a irritating (to me anyway) I understood it to mean it could not have happened. I have learned that pH can be changed not only by adding Co2 or a changing alk but also by adding acids or caustics. All I was saying was look for an alternative source of low pH that may not be related to the usual test kit parameters.

As for as the Kalk not workig as a buffer, it never did for me. My alk doesnt change wether I use it or not.

Hope this clears things up a bit

dzhuo
10/12/2011, 11:56 AM
OK, sometimes things can be read or understood online not as they are intended.


That's why I always provide extra links to the quotes where the discussion happens.

I have learned that pH can be changed not only by adding Co2 or a changing alk but also by adding acids or caustics.

Adding acids would lower your alk which would lower your pH.


As for as the Kalk not workig as a buffer, it never did for me. My alk doesnt change wether I use it or not.


That's the point of using kalk to maintain pH without drastically altering alk. If kalk did in fact raise your alk substantially, then it won't be a good pH solution.

I want to correct a typo I made earlier where I said 15% of saturated kalk would raise 0.3 unit of pH. I was wrong and it should be:

Problem Dinoflagellates and pH (http://www.reefkeeping.com/issues/2006-11/rhf/)

As a general guideline, adding the equivalent of 1.25% of the tank's volume in saturated limewater will raise the pH by about 0.66 pH units.