kalkwas = 8.6 pH

[serotonin]

I started adding kalkwasser to my tank via a 1gal milk jug, 1/4" tube and a vice grip to clamp the hose down. I add around 1 drop per second or so. I use 3/4 tsp (not sifted measure, but packed dense) per 1 gal of mix. I've been making 1 jug a day and pouring it into my dosing jug every evening. I bought a pH meter on Saturday, so I haven't been religious about taking pH measurements. Plus the 5drop +5mL water test kits w/ the purple color are just terrible for me as I can't tell the diff between 8.4 and 8.8 with those types of kits. ANYWAYS ( ), I have been measuring my pH like crazy lately and I've noticed it to be pretty much stable at 8.5 to 8.6. While not terrible, I read this precipitates PO4 which I did have a trace of the last time I tested, I'd rather have my pH a couple points lower. I can't be certain it's the kalk, I did stop the drip last night and this morning my pH was still 8.5. I did slowly add a tbsp of baking soda to the prefilter before going to work to try to counter the pH a lil bit at least. All the life in the tank seems happy thankfully

Please share your thoughts & concerns

EDIT: I forgot to add that I'm leaning towards adding vinegar to my kalk to help combat the pH issue.

[inwall75]

If your pH was 8.5 in the morning and you haven't dripped any Kalk, my thought would be that the reagents in your pH test kit are off.

What brand pH meter did you buy and how did you calibrate it?

[Boomer]

First, there does not seem to be a reason to add vinegar to your kalk, unless you are having a Ca++ issue. Your mix is well under saturtated at 3/4 tsps / gal and you are not having issues where vinegar is needed. Kalk Saturation is 2 tsp / gal. Kalk can drive up the pH and Alk. So what is the Alk and Ca++ ? Are you using just kalk for Ca++ and Alk sup's ?

1 liter of saturated kalk will drive the pH up about .15 units / 100 gal net tank water. If anything lower the amount of kalk to the water being added to 1/2 tsps / gal. For now, just let the pH fall on its own and then restart things up. Your pH will drop faster than you think. I might add some people which using kalk dosing run their pH up to 8.5.

Who's pH test kit are you using ? I would get a Aquarium Systems SeaTest/FasTest pH kit, which is about the best pH test kit there is. You just fill the vial and add a powder and there is a quick color change. The kit goes from 7.8-8.6.

I might add the vinegar can also fuel bacteria and algae. If you need more CO2 to keep the pH in check I would go with Seltzer water. Vinegar can also cause other problems, such as binding to metals and making them more soluble.

[serotonin]

My wife just poured about 4-8 cups of my kalkwasser into the sump b/c it was starting to draw air. (yikes) She called me at work and told me about the air problem. I immediately asked her what bottle she used, it was my Kalkwasser

She proceeded to check the pH which spiked to 8.8. I then instructed she start adding baking soda to the system to get the pH down to 8.6 at least. We use a pH pen that I feel is quite reliable to check our pH.

kalkwasser recommends that vinegar isn't necessairly as bad as thought. I'll have to leave any argument here as I'm not a chemist.

My alk is off the charts, calcium is at 420, the pH is now stable at 8.5. Hats off to my wife, she did a good job under the panic she was in She was not aware that kalk has a pH of 12 or so, but I doub't she'll ever forget that now, lol!

EDIT: when you are measuring your kalk, do you pack it down or leave it in the soft, sifted state?

EDIT2: You know, it's some new disaster every week lately (with me)! :O

[Boomer]

Baking soda will not do much to lower the pH. The pH lowering for baking soda is only initial, till the CO2 has been driven off due to its addition. The pH will then go back up to about where it was. You never add baking soda to lower pH. It will for sure raise your Alk even more. Baking soda is a buffer and raises the Alk as does kalk. Both also raise the pH it is just that Kalk raise it more. Adding the baking soda just raised the Alk even more and did much of nothing for the pH, if anything at all. The lowering of the pH more than likely would have happen without the baking soda. Can, will baking soda lower pH ? Sure, in a very high pH solution. Most of the buffer in seawater, like 85 % *Bicarbonate @ 8.3 pH and drops about 3 % / .1 pH unit rise in pH. Baking Soda is NaHCO3 or Sodium *Bicarbonate.

The pH of saturated kalk water is almost 12.5 @ 77F.

When ever adding a granular or powder substances to a teaspoon you just fill it and then plow off the excess with the back of a butter knife. That is 1 level tsps and is what we go by.

kalkwasser recommends that vinegar isn't necessairly as bad as thought.

That is not always so though. It works good at times for some but not for all. Allot depends on the system. It is only suppose to be use if used in saturated mix of kalk in water and you are not at a saturated mix, which is 2 tsps / gal. Its purpose is to allow more kalk to dissolve in solution. Seltzer water is better for lowering the pH but will do nothing for your Alk. I might add that vinegar can also drive up the Alk even more. It is a complex issue. It is best left to those that need it and have a reason for it, other than just trying to lower the pH which is your issue.

With the issues you have now created you have the potential of having a snow storm ( water turning cloudy) with the Alk and pH so high. What ever you do not let the Calcium get any higher. It may be that with the pH and Alk that high the calcium will drop. As it drops it will lower the Alk and pH. You may see a white chalk on the bottom and collecting on hot/warm objects like the heater and internal pump housing.

There is no good way to lower the Alk that is that high other than multi-water changes to get it and the pH in check.

[serotonin]

The pH is down to 8.5 and not moving. This is .1 lower than what it has been for the past couple days.

Thanks a lot for the advice about the baking soda! My alk is off the scale I'll get that down with a couple water changes.

Ill keep a close eye on the alk that's for sure. SHEESH..

thanks again

[Jason McKenzie]

Originally Posted by inwall75

If your pH was 8.5 in the morning and you haven't dripped any Kalk, my thought would be that the reagents in your pH test kit are off.

What brand pH meter did you buy and how did you calibrate it?

I agree have you Calibrated your meter?

J

[serotonin]

The slip that came with it said it was pre-calibrated. I have compared its reading to my liquid-color test kit and they appear to match.

Alas, the simple answer is I myself have not checked the calibration.

EDIT: doing a 15 gal change tonight, thankfully had some water ready. Boy do I feel like a jackass

EDIT2: Water change done, pH is still 8.5, alk is at 16 dKH, calc is 420.

I'll setup for a 20 gal water change and get the dKH down to semi-acceptable levels this weekend. Sound like a decent plan?

[Boomer]

Take that meter and check the pH of the new salt mix.

[serotonin]

pH of the new salt mix was 8.3. That being the the 15 gals I had made up, RO/DI and instant ocean salt, no other additives