Increasing both Ca and Alk Question

[ostrow]

Randy:

A first for me. Both dKh and Ca are lower than I want, 9 and 350 respectively. I want to raise to 12 and 445.

Only reason I want to raise alk from where it is is b/c of some cyano (or dinos? or diatoms?) ... indicated by scum on the surface of the tank water. Some suggest raising alk so I want to try that.

Calculator says 15tsp of Turbo Ca and 3tsp of soda ash. But I am assuming I have to add one today and the other after several hours (tomorrow). Right? Adding both within a short period of time = precipitation, no?

[Randy Holmes-Farley]

OK, I don't know what effect it might have on the algae, but raising alkalinity should be straightforward. :)

You can add both separated by enough time for the first to mix in fully (a couple of minutes in a sumpless system to an hour or two in some extended sump/refugium systems). Dissolve each in fresh water.

[ostrow]

thx

[Randy Holmes-Farley]

You're welcome.

Good luck with the algae. :)

[Montreal]

Is it possible to have a Ca at 600 I've tested it...with 2 tests kits, how can I reduce it.

[Nemo_0916]

Montreal ... from what I understand (what Randy told me actually :) ) you do not do anything to lower calium except wait patiently and allow the system to 'use up calcium' thereby bringing it down naturally ....

[Randy Holmes-Farley]

It is certainly possible to have calcium at 600 ppm. The first step is to figure out how it got there. Overdose of a supplement? The use of Oceanic salt mix? Long term use of a balanced calcium and alkalinity additive plus a buffer or other alkalinity only supplement?

The next step is to measure the alkalinty, and possibly pH, to see how to make a correction. This article details that process:

Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm

[Montreal]

I'm using a redsea alk tester, it reads low-normal. I don't get an exact vlaue. my PH 8.3 Should I do a water change %10. I'm using a RO.

[Randy Holmes-Farley]

I'd suggest getting an alkalinity kit that gives an actual reading. Seachem, Salifert, LaMotte and Hach have fine alkalinity kits.

A water change won't help if the water change water has elevated calcium as well. That's one reason to figure out why the calcium is high.

What salt mix are you using?

[Montreal]

I got another Ca tests and it reads 500ppm. I checked my No3 that was the prob I was very high! I don't know why? I don't over feed. I have a big refug and sump. great water cyrcl. I've added sugar, it helped in the past....THANKS

[Nickeleye]

I don't mean to hijack the thread or anything, but I seem to be having a similar issue in my 12 gal. nano. Where the water isn't being constantly disturbed by the powerhead there seems to be a faint milky looking film on the water. I measured my calcium levels and they look to be a bit high... probably around 550 or so. Then I tested alk/kh and I ended up with about 2.9 on alk and ~8.2 on KH. Then I tested PH and I'm showing somewhere in the neighborhood of 7.8. I think I know the cause of the calcium (dosing... whoops...), but I'm not sure what to do about the PH and KH. Alkalinity appears to be good, right? I still don't have a firm grasp on these tests and what to do with the results. Maybe somebody could help me and Ostrow.

[Randy Holmes-Farley]

I got another Ca tests and it reads 500ppm.

500 ppm calcium is not much of a concern. No need for a water change. The water may even be the source of the high calcium. If you want to lower the calcium, just supplement alkalinity over time with an alkalinity only supplement such as baking soda. Then when the calcium hits 450 ppm, resume using some sort of balanced calcium and alkalinity additive, as described in this article:

How to Select a Calcium and Alkalinity Supplementation Scheme
http://www.advancedaquarist.com/issues/feb2003/chem.htm

[Randy Holmes-Farley]

Where the water isn't being constantly disturbed by the powerhead there seems to be a faint milky looking film on the water.

Most often, that is dust and organic materials, not CaCO3 precipitation. Surface skimming and surface agitation are the best ways to remove it.


linity appears to be good, right?

Yes, that is fine. My suggestion is to use an alkalinity only supplement until the calcium declines to 450 ppm. Bakign soda is a fine choice, but I'd bake it before use to help raise the pH. t

Then use a balanced additive system, such as a two part additive, to maintain both calcium and alkalinity. The high pH types (such as B-ionic or my DIY using baked bakign soda) will help keep the pH higher.

These articles may help:

Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm

Low pH: Causes and Cures
http://reefkeeping.com/issues/2004-09/rhf/index.htm

How to Select a Calcium and Alkalinity Supplementation Scheme
http://www.advancedaquarist.com/issues/feb2003/chem.htm

A Homemade Two-Part Calcium and Alkalinity Additive System
http://www.advancedaquarist.com/issues/april2004/chem.htm

[ostrow]

I lowered then raised my overflow box, basically kept adjusting until surface skimming was more vigorous while not raising the water level unacceptably high. Course, I thought I had it there months ago so why I had to suddenly adjust is beyond me, but such is life!

Also skimming more on the wet side, running carbon.

The muck is mostly gone. Probably those things did it, not raising my alk.

[Randy Holmes-Farley]

Skimming and carbon should decrease it, but once on the water surface, only some sort of surface overflow or turbulance will get rid of it. Hopefully some more twiddling will help. :D

FWIW, the coating does deter gas exchange, so it best removed.

[reefer4411]

i am new today so i aplogize if this may be inapropreate but the was fighting a cyano problem and just happened to notice that my alk was droping so i brought it back up and all the cyano diapeared this later made sense to me when i was told cyano may begin to form from parts of ones tank that may trap phospates which in turn cause a slightly altered ph it is my understanding that a alkalinaty or buffer level increase will prevent alterations in ph

[Randy Holmes-Farley]

i am new today so i aplogize if this may be inapropreate

Welcome to the Reef Chemistry forum. All opinions and comments are welcome. :)

In general, elevated phosphate doesn't cause altered pH.

It is possible that low alkalinity leads to low calcification and growth, and hence low phosphate consumption by hard corals coralline algae, and that the phosphate is then more available for cyano.

Low pH also leads to poor calcification and growth, and if you raise pH through whatever means, corals and coralline algae may grow more, depleting phosphate.