Calcium and dKH Struggles

[steve-s]

Could my entire problem here be that either I have been targeting too low of a S.G. and/or my hydrometer is reading too high? The IO folks recommended targeting 1.026 or 1.027.

Which is why I suggested increasing your SG up to 1.025, it's part of your problem but not the main issue. IO salts are still Ca deficient. If you had a refractometer I would have suggested 35 ppt (1.027 SG) which is NSW and where most salts are made to work best. Many salts are "designed" if you will to work differently at a given salinity. Increasing the salinity will increase the chem along with it. One reason I urged you to do the same with the main (via water changes) in order to make this a bit easier.

If using SW at lower than recommeneded concentrations, your water changes will eventually bring the tanks chemistry in line with that of the saltmix depending on amount/frequencey changed. If in conjunction with dosing, you an easily end up with skewed numbers.

As far as the accuracey of your hydrometer, soak it overnight in a 10:1 water/vinegar solution, rinse in hot water the next day and let air dry. Retest and see if that was part of the problem. One reason to always suggest 1.025 when dealing with hydrometers is their inaccuracey is pretty much a given, especially if the unit is seen some use. With a refractometer you simpley need target 35 ppt and be done with it.

Cheers
Steve

 

[awillemd1]

You are awesome Steve-s. Thank you once again!

I am on vacation now, but I will get back to it when I return home in about 10 days.

Willem

 

[awillemd1]

FYI.

Anyone who was following this thread, the folks at Aquarium Systems, i.e. the makers of Instant Ocean salt, sent me the composition of their salt at 35 ppt salinity. If you send me a PM, I will be happy to forward this to you.

Willem

 

[awillemd1]

Steve-s:

I am back from vacation and anxious to get the chemistry in my tank correct.

I have made a new batch of salt water and carefully brought it to a 1.026 hydrometer reading. The Magnesium level is now reading 1275, but the Ca level is only 370 ppm. It would typically be 350 when I was going to a 1.024 hydrometer reading and the Mg level was around 1000 ppm.

So I have raised my Mg by about 30%, but my Ca has only gone up by about 10%. This is very strange to me.:? The gentleman at Aquarium Systems indicated that at a Specific Gravity of around 1.026 or 1.027, i.e. the value for NSW, the Ca level should be 400 and the Mg level should be 400. One observation I have made is that I am constantly having to clean a crust off of my the cooler. This crust is an off white color and it seems to dissolve in vinegar fairly easily making me think it is calcium.

My plan now, per your advice, is to bring the Ca level up to around 415 and perform several 10% water changes until my aquarium has the correct chemistry, i.e. dKH, pH, Ca and Mg.

Any thoughts on the weird Ca result would be most appreciated.

Willem

 

[awillemd1]

Steve-s:

Here is the update on my attempts to improve the chemistry in my aquarium.

I took my hydrometer to an aquarium store in Houston, about an hours drive away, and they verified its accuracy using a refractometer.

I have performed about 6 water changes using the IO salt with target salinity of 35 and addition of additional calcium.

I purchased the Kent Turbo Calc.

My aquarium is now at Ca = 400, dKH = 2.5, and salinity between 35 and 36.

I think you indicated that these were good numbers, with the exception of the Ca which is slightly low, but probably within experimental error.

Also, I clearly am seeing increased growth of Coralline Algae as I indicated in another post.

It does seem that my Ca is holding much better than before and that no matter what I do the dKh wants to be at 2.5.

I plan to start dripping Kalk again to try and maintain these values.

Do you agree? Is there anything else I should be doing?

Thanks in advance.

Willem

 

[steve-s]

My aquarium is now at Ca = 400, dKH = 2.5, and salinity between 35 and 36.

I think you indicated that these were good numbers, with the exception of the Ca which is slightly low, but probably within experimental error.

These numbers are looking much better. I would still eek up a tad more but not imperative.

Also, I clearly am seeing increased growth of Coralline Algae as I indicated in another post.

Good sign...

It does seem that my Ca is holding much better than before and that no matter what I do the dKh wants to be at 2.5.

In relation to? With or without dosing and how long between water changes? What you could easily be seeing is normal usage. How's the Mg level?

I plan to start dripping Kalk again to try and maintain these values.

Do you agree?

You can yes, I would not go full out though. Depending on your tanks evap rate, start slow. Use a weak solution of limewater to start off with ½-1 teaspoon per gallon. Drip, test and post back with the changes the day after and the next day. The idea being to get some idea of rate of depletion. The ideal situation for that is get the chem up to NSW values and test every second day for a week while not performing any water changes or dosing anything. This will help you to guage what is needed and how often. Otherwise it's a bit of guess work.

Is there anything else I should be doing?

Just keep testing and be sure to keep up with the water changes. Also try to get it so that what you dose (if needed) is done as much on a daily basis as possible. Even if your adding wee amounts. This will be much healthier for your system and help prevent future imbalances from larger less frequent additions.

Cheers
Steve

 

[awillemd1]

Steve-s:

Here is my update:

How's the Mg level?

1240 ppm

The ideal situation for that is get the chem up to NSW values and test every second day for a week while not performing any water changes or dosing anything. This will help you to guage what is needed and how often. Otherwise it's a bit of guess work.

OK. I didn't dose anything and I didn't perform any water changes. Here are my testing results.

8/13 Ca = 400
dKh = 2.5 meq/l

8/17 Ca = 400
dKh = 2.74

8/19 Ca = 400
dKh = 2.5

8/21 Ca = 390
dKh = 2.74

It looks like things a stabel over a weeks time anyway.

I guess my plan from here is to get the dKh up slightly and the Ca up slightly. It seems like the best way to do this is through dripping Kalk, but I will wait to here what you advise.

Willem

 

[steve-s]

I guess my plan from here is to get the dKh up slightly and the Ca up slightly. It seems like the best way to do this is through dripping Kalk, but I will wait to here what you advise.

I would definately not use the kalkwasser as a means of control with so little movement in your numbers for one week. Your alk is fine for the most part although your Ca could come up some. 2½ teaspoons of dry CaCl (broken up & added over a few days time) would fix that up easily enough.

You can drip a weak solution of kalk if you already have it but I would dissolve ½ a teaspoon of kalk powder in 1 gal of water drip, test and most likely you'll need to do the same a day or two later to get the desired results. Since there was little or no depletion, this would be a "repair" of the current chemistry not a regular routine. I don't see how you would need to do this all that often. I think if you tweek the SW used for your water changes before use to the chemistry desired, you'll be able to maintain it just fine without adding chems to the tank.

Cheers
Steve