issue with Ph

02tts · Aug 21, 2008

So I have a wet/dry system from lifereef and a skimmer from him as well on a 265G tank, that being said, I'm having an issue maintaining an acceptable pH level....I can not for the life of me keep it about 8.15 from 6-1am and 8.11 the rest of the time (lights come on at 4pm), tank temp is ketp at 79 with a chiller. Here are rest of water values:

Ammonia: 0
Nitrites: 0
Nitrates: 20
Salinity: 1.022
Calcium: 417
ORP: ~340 (no ozone used)
Alkalinity: 3meq/l (8.4 dKH) [have tried up to 4meq/l or 14dKH]
pH: 8.11 - 8.15 ( I would really like to achieve 8.25 to 8.3) (as you can see, the swing is not that big, and would not be noticeable on a chemical test kit, but I can not get passed 8.16, 8.17 no matter what I do).

Things done to test to see if anything might be causing it:

1. removed all sand, and all live rock,tank is empty with just fish - only 10 small fish - same thing, no change
2. cleaned out all filters and skimmer - nothing since everything was already cleaned
3. remove glass canopy's in case too much CO2 was getting trapped in the tank - no change, which means I don't have a CO2 problem
4. added two 4" airstones to the sump - went up by .02 (I have a two different types of digital readers)
5. tried new CaribSea Aragamaz Select Dry Sand which - no change

Products Tried to bring pH up:

1. Natureef Seal Alk
2. Kent Marine pH buffer
3. Seachem Marine Buffer (blue label)
4. Seachem Marine Buffer (purple label)

Even more simple test to determin cause:

1. took tank water and let it sit outside of tank for up to 8 hours - no change
2. took tank water and let it sit for up to 8 hours with an air stone - and pH went to 8.24 to 8.25 and stayed there!!!!

So...what does does this all mean...to me, it would sound to me, and I'm no chemist or expert on this, but that the tank is somehow low or being starved of oxygen...could this be the case...and if so, what is the solution...I don't want to have to put airstone inside the tank!

Help please, this is driving me nuts!

p.s. - would this have an affect on high nitrates...I would think so but I need some expert opinions.

Jay.B. · Aug 21, 2008

I am no expert by far, and completely unfamiliar with your filtration system having never used a wet/dry system before....

but... having said that, if adding an airstone to a container of water solves the problem on a small scale (higher co2 than o2 does make things a little more acidic) put a power head just under the surface to create a greater disturbance on the waters surface... that will help gas exchange both ways, salt water doesn't hold o2 as well as fresh, so the larger the surface area for the disturbance the better and it'll hopefully go part way to solve it... I'm no use after that unfortunately, new to this side of fishkeeping myself

addition...

what type of sand are you using... crushed coral? aragonite? normal aquarium sand? the first two should be very good pH buffers, hopefully you're using one of those

02tts · Aug 21, 2008

On the sand, yes, if you look at line item 5 you'll see I'm now using CaribSea Aragamaz which is dry aragonite sand, as supposed to live sand

Problem is not with swings, I don't have large pH swings, just not able to go above a certain range no matter what I do, water changes, etc...

so a few things I forgot also:

1. yes, I have tried to do more of a riple effect on the water using the return pumps - while this raises the pH a bit, to around 8.19 it evaporates a tremendous amount of water, enough to make it rain inside my house!

2. I have a korolia 4 pump inside the tank circulating the water from end to end so as to ensure no "dead spots" where water could get stagnant and bacteria grow, values be affected, etc, etc...

3. I have changed return pumps to ensure more than enough flow (my overflows are 1" x2, hence a total of 1200GPH) - I'm using a Reeflo Wahoo pumps valved down to ensure accurate flow - interestingly, before I had an underpowered pump and no change in pH

I think that about covers it, but it all really boils down to the simple water test, if I aerate it outside the tank with a small airstone pH gets to 8.24 / 8.25 which is perfect....so what's my issue and how do I fix it without creating an amazon inside my house.

Jay.B. · Aug 21, 2008

could it possibly be the brand of salt you're using, I know they're all pretty similar now, but some have more built in buffers than others...

that's the only other thing I can think of at the moment that could possibly negatively affect pH ... how about maybe upping your SG to 1.024 or 1.025

Amphiprion · Aug 21, 2008

Just because you removed the lid doesn't necessarily mean there isn't a pH issue. Houses, etc. are typically higher in CO2 to begin with, which could easily cause a lower pH. What I am trying to figure out is why you want to raise it when it is fine where it is. The things you used to raise pH are either extremely transient won't necessarily do much good. This is primarily in reference to the buffer solutions added, which appropriately raise alkalinity, but not really pH. If you genuinely feel you must raise the pH (which isn't necessary at all in your case), I recommend adding kalkwasser, which will also satisfy your calcium and alkalinity needs, making it a balanced supplement. Again, you don't really need to raise it, but kalkwasser would be a fine route to try if you want to. In fact, it will raise the pH by a lot if you don't add it judiciously.

02tts · Aug 22, 2008

CO2 in house is fine...if I take tank water and let it sit outside, the pH only increases by .02 vs. water on the inside of the house.

Amphiprion · Aug 22, 2008

02tts said:
CO2 in house is fine...if I take tank water and let it sit outside, the pH only increases by .02 vs. water on the inside of the house.

Then I wouldn't be concerned with those levels. A pH of 7.8-8.5 is acceptable, with natural seawater averaging around 8.0-8.3. Calcification in corals is optimized at around 8.4.

02tts · Aug 22, 2008

ok...i'll keep an eye on it...today it's at 8.03, once lights come in at 4pm it may get to as high as 8.1, but prob. not higher...it's just odd, extremely odd that I can't seem to get it higher...remember, aerating the water with an air stone brings pH to 8.25 so it's obviously lacking O2 in the water...and I've tried just about everything, I actualy have two koralia magnun 6's coming tomorrow to put one at each end of the tank in hopes that much circulation enhances gas exchange and brings pH up...but somehow I highly doubt it will make a diff.

snailrider · Aug 22, 2008

Hi, I was wondering if you bumped your salinity a bit if that might help.

I run about .023-.024, (swingarm) arogonite in sump, just started dosing with nano reef-more for nutrients and minerals.

My ph is at 8.3 give or take a little (test strip) and alk is at 80.

I use tap water exclusively. And my Live Rock is man made with my own recipe. I had to monkey around a bit to get the recipe right, as to not kill the ph either direction.

for awhile, the first rocks were making my tank go acid, then they went the other way. Now, the last rocks I added to my 55, the ph has not changed. I also forgot to mention I do use the mineral block by sea lab #28.

Amphiprion · Aug 22, 2008

02tts said:
ok...i'll keep an eye on it...today it's at 8.03, once lights come in at 4pm it may get to as high as 8.1, but prob. not higher...it's just odd, extremely odd that I can't seem to get it higher...remember, aerating the water with an air stone brings pH to 8.25 so it's obviously lacking O2 in the water...and I've tried just about everything, I actualy have two koralia magnun 6's coming tomorrow to put one at each end of the tank in hopes that much circulation enhances gas exchange and brings pH up...but somehow I highly doubt it will make a diff.

Oxygen doesn't really have an effect on pH, but carbon dioxide does. The only reason people with refugia, fw planted tanks, etc. get higher pH values (unless the latter is CO2 injected) is because of the consumption of CO2, not the production of oxygen. People often correlate the two because of photosynthesis, but that is not the mechanism of the change in pH. I am confused, though, since you say aerating it brings it to 8.25. When you brought the tank water outside, did you aerate it overnight? Allowing it just to sit will take MUCH longer to equilibrate, giving a false reading. If you aerate the water and it raises the pH, then CO2 is causing the problem.


zoomed.com	hikariusa.com		aqaimports.com	Store

Search

Search

issue with Ph

02tts

AC Members

Jay.B.

Puffer Lover

02tts

AC Members

Jay.B.

Puffer Lover

Amphiprion

Contain the Excitement...

02tts

AC Members

Amphiprion

Contain the Excitement...

02tts

AC Members

snailrider

AC Members

Amphiprion

Contain the Excitement...