Two Part Dosing

[divecj5]

Quick question about two part dosing. I am not new to dosing two part solutions but I have been struggling to get all of my parameters in line....well at least to keep stable.

 

I have been using Two Little Fishes C-Balance Part A and B for my dosing. I have recently started keeping a real keen eye on my parameters with daily testing to make sure that I try to keep them as stable as possible. No corals (including some new montis and birdsnest) have shown any signs of problems but I just want to get my dosing under control.

 

I have been seeing a slow incline in Alk while Ca is holding steady. From all that I've read, a 1:1 consumption rate would be 1 dk per 20 ppm Ca utilized by the corals. I have been dosing the same amount of the two part solutions since I thought this helped to keep ionic balance. Here is where things tested last night:

 

Alk: 14 dKH (too high IMO)

Ca: 380 ppm

Mg: 1250

 

I don't see anything wrong with these other than I would like to get Ca higher and have Alk come down to around the 9 dKH range.

 

Question is whether it is ok to dose say more of the Ca additive than the Alk additive? I would think this would be ok but just wanted to check what you all thought before doing this. I would think this would help to solve my imbalance.

 

Thanks in advance for any help.

[StevieT]

IME it is best to keep dosing with equal parts, but someone else can probably chime in and help the imballance

[sl-atl]

IME it is best to keep dosing with equal parts, but someone else can probably chime in and help the imballance

 

I've heard the same- it's best to dose with equal parts. You've probably seen this article, but just in case you haven't it is an awesome discussion of reef chemistry and the why and hows of using 2-part supplement systems. http://reefkeeping.com/issues/2007-04/rhf/index.php

 

The only thing I can think of otherwise is how is your pH trending? My understanding is that inadequate gas exchange (CO2 and O2) can make maintaining pH and alk. challenging, but fortunately that's an easy fix.

[SPS20]

There is no great crime in dosing 2-part solutions unequally, however, I would suggest a slightly different approach. If I were you, I would reduce the amount that you dose such that the Alk holds steady and the Ca+ falls slowly, and then begin supplementing the Ca+ with some other supplement to keep it steady.

[rhunter513]

This article really helped me.

 

http://www.advancedaquarist.com/issues/nov2002/chem.htm

[divecj5]

I've heard the same- it's best to dose with equal parts. You've probably seen this article, but just in case you haven't it is an awesome discussion of reef chemistry and the why and hows of using 2-part supplement systems. http://reefkeeping.com/issues/2007-04/rhf/index.php

 

The only thing I can think of otherwise is how is your pH trending? My understanding is that inadequate gas exchange (CO2 and O2) can make maintaining pH and alk. challenging, but fortunately that's an easy fix.

 

Thanks for the reply and the link to the article. My pH has been holding pretty steady between 8.1 and 8.2 so not sure if that is an issue. I get a lot of surface agitation and tumbling of the water in the rear chambers of the BC.

 

 

There is no great crime in dosing 2-part solutions unequally, however, I would suggest a slightly different approach. If I were you, I would reduce the amount that you dose such that the Alk holds steady and the Ca+ falls slowly, and then begin supplementing the Ca+ with some other supplement to keep it steady.

 

Just to make sure I have this right with your approach....just dose a little less to let Alk fall from where it is now. Once it has fallen to a certain level, start dosing another Ca supplement other than the two-part?

[SPS20]

Just to make sure I have this right with your approach....just dose a little less to let Alk fall from where it is now. Once it has fallen to a certain level, start dosing another Ca supplement other than the two-part?

 

Before you do anything else, I would first suggest making sure all your parameters are in line with where they should be. In your case, this would mean not dosing any Alk supplements at all until your Alk readings fall to desired levels. I would continue to supplement Calcium at the rate you were before, but keep in mind that it will be nearly impossible for you to get your Calcium readings much higher until your Alk has fallen to normal levels. Don't sweat that too much just yet, instead focus on getting your Alk down a bit, which is something that will naturally happen over time anyway.

 

The article linked above (http://www.advancedaquarist.com/issues/nov2002/chem.htm) is a really good guide to correcting out-of-whack Alk/Ca+ readings. It should be your bible for the corrective measures you must take.

 

Once your water chemistry is back to normal, then the task becomes one of maintaining appropriate levels. It is not entirely uncommon for users of two-part additives to experience a drift of one or both of Alk/Ca+ out of desired parameters. Not every tank consumes them in lock-step with each other, and this is not neccessarily indicative of a larger problem. I use a two-part additive (B-ionic) and have at time had experiences similar to yours.

 

There are several ways to deal with such a situation. One approach, which I personally do not favor, is to dose a little more of one half of the two-part than the other. This will work, but may ultimately throw your secondary minerals out of whack (Sr/Mg/etc) and will result in the annoying circumstance of having one empty bottle, and one partly full. Instead, I would suggest dosing both parts in the same amount, but only enough such your Alk levels remain stable, and your Ca+ levels slowly fall. (or vice-versa, whatever the issue happens to be) Then, supplement the parameter that tends to trend more strongly downward with another, separate supplement. I would recommend the Seachem products, they have worked well for me. (I think Reef Calcium is the one I use, but i'm not sure as I am not at home to look at the container.)

 

Keep testing, as the demand for Ca+/Alk in your tank may change over time as corals grow and the tank matures. I hope this information proves useful. Keep up on your regular water changes, as nothing else you do will matter at all if you don't. Nothing corrects the small sins of husbandry like water changes.

 

- Josh