How much (Ca, Mg, Alk) is too much to add in a single dose?

[Sailor]

There are charts available everywhere that list ideal water parameters for any type of system (like a mixed reef, SPS dominant, natural seawater, etc.). But what is not at all clear is how much of any particular supplement you can safely add at any one time to bring your current water chemistry up to chart specifications.

For example, the labels Red Sea Foundation B and C clearly show that 1ml of supplement per 100 liters of water will raise the alkalinity by 0.1 dKH, or the magnesium by 1 ppm. Okay, fine. The label on the back goes a step further. It shows the total amount needed to bring your current level up to the desired level. Again, okay, fine! In my case, the last ICP test reported Mg at 1180 ppm, and since the target level in my mixed reef tank is 1350, the chart says I need 170 ml per 100L, or 680 ml in my 400L system.

Surely, they’re not telling me to dump the entire 500 ml bottle and half of another one into the tank at one time! That’s insane! So, how much is too much?

I’m not asking how much of any manufacturer’s product to add to any particular tank, but rather where do you draw the line for any particular parameter. In other words, how many parts per million can you safely raise the magnesium level in a single dose? How much dKH can you bump up safely in a single dose? Again, I’m not asking how many drops, or milliliters, or ounces of supplement to add. I’m asking how much of a change in solution (expressed in ppm or dKH) can the aquarium inhabitants tolerate when that change occurs instantaneously?

 

[fishski13]

Yeah you don’t want to change parameters too much too fast. Not sure about calcium or magnetism as I never had problems with it but I was always thought never to change alkalinity by more than 1dkh at a time.

 

[V A R I A N T]

Aquarium and Reef Calculators - Bulk Reef Supply

Bulk Reef Supply - Saltwater Aquarium Supplies for Reef Tanks

www.bulkreefsupply.com

 

[Sailor]

Thanks for the tip, guys, but that doesn't really help at all. The reef calculators tell me how much of a given product to dose to get me from Point A to Point B, but then they all say "Do not dose all at once". I ALREADY KNOW THAT!

Perhaps I should rephrase my question: Instead of how much can I safely raise the ppm in a single dose, I should have asked how much of a change in parts per million of a given supplement can a stocked aquarium tolerate in a single day?

It is safe to increase total magnesium by ___ ppm in a single day.
It is safe to increase total calcium by ___ ppm in a single day.
It is safe to increase total alkalinity by ___ dKH in a single day.

 

[V A R I A N T]

Alkalinity: If making a large adjustment (more than 1.4 dKH) divide the dose up and add to the tank over the course of 1-2 days to avoid dramatic changes in water chemistry. Implies not more than 1.4 dKH per day.

Calcium: If making a large adjustment (more than 50 PPM) divide the dose up and add to the tank over the course of 1-2 days to avoid dramatic changes in water chemistry. Implies not more than 50ppm per day.

Magnesium: If making a large adjustment (more than 100 PPM) divide the dose up and add to the tank over the course of 1-2 days to avoid dramatic changes in water chemistry. Implies not more than 100ppm per day.

 

[homer1475]

I usually do not go over 1.5 DKH of alkalinity, 50ppm calcium, or 100ppm magnesium in one shot. I have on occasion gone as far as 200ppm mag and did not have an issue, but try to stick to what I've read, and what I recommend above.

 

[Randy Holmes-Farley]

There are charts available everywhere that list ideal water parameters for any type of system (like a mixed reef, SPS dominant, natural seawater, etc.). But what is not at all clear is how much of any particular supplement you can safely add at any one time to bring your current water chemistry up to chart specifications.

For example, the labels Red Sea Foundation B and C clearly show that 1ml of supplement per 100 liters of water will raise the alkalinity by 0.1 dKH, or the magnesium by 1 ppm. Okay, fine. The label on the back goes a step further. It shows the total amount needed to bring your current level up to the desired level. Again, okay, fine! In my case, the last ICP test reported Mg at 1180 ppm, and since the target level in my mixed reef tank is 1350, the chart says I need 170 ml per 100L, or 680 ml in my 400L system.

Surely, they’re not telling me to dump the entire 500 ml bottle and half of another one into the tank at one time! That’s insane! So, how much is too much?

I’m not asking how much of any manufacturer’s product to add to any particular tank, but rather where do you draw the line for any particular parameter. In other words, how many parts per million can you safely raise the magnesium level in a single dose? How much dKH can you bump up safely in a single dose? Again, I’m not asking how many drops, or milliliters, or ounces of supplement to add. I’m asking how much of a change in solution (expressed in ppm or dKH) can the aquarium inhabitants tolerate when that change occurs instantaneously?

I think you may just be looking in the wrong places since I’ve made these suggestions hundreds of times in many articles and threads.

There is no magic number for any of these, and the reasons to control them are different for different parameters.

My suggestion for calcium and magnesium is to limit the boost to 25-50 ppm per day due to the potential for impurities in the chemicals, not because of the Ca or Mg itself. The purer the dose, the more it is ok to boost at the higher end. It is also very rarely needed to boost faster. If there is a need for a big boost, it may be test error.

Alk boosting is more problematic because coral growth is often alk limited and hence alk is a more critical change. Raising the average level by 0.5 dKH per day seems generally safe. Again, rarely is more needed any way. Of course, a tank may use much more each day, so dose whatever is needed to keep the average level where you want it, and if you need to dose more than 0.5 dKH per day, consider splitting the doses or use a dosing pump.

 

[Sailor]

Okay guys, thanks for the replies. Let me summarize what I’ve learned so far. My question was, how much of a particular supplement can I safely dose at any one time. And the best answer I got was:

“There is no magic number.”

Seriously, that really is the best answer. Essentially, Randy is telling me to slow down, be careful, and don’t over-dose! I can understand from a purely mathematical perspective how the reef calculators or the charts on the supplement packaging can tell you precisely how much product is required to get from Point A to Point B. But I can only imagine why they don’t tell you exactly at what rate to apply the product — all at once, or spread out over time… a day, a week, whatever. Perhaps it’s a liability issue. The manufacturers don’t want to commit to a specific dosage rate because there are too may variables and every system is different.

In any case, now I’m back to Square One. Except that you guys did offer some suggestions. I’m just having a problem wrapping my head around those numbers… they seem rather large, perhaps even excessive. Let me explain, and please correct me if I’m wrong.

Regarding magnesium, Variant says “not more than 100 ppm per day.” Using the example in my initial post, 1 ml of the Red Sea Foundation C supplement per 100 liters of water will raise the magnesium level by 1 ppm. So, in a 100 liter (25 gallon) aquarium, it takes 100 ml of supplement to raise the Mg level by 100 ppm. My tank is 400 liters, so I would need 400 milliliters (or 13.5 fluid ounces) of that supplement to bump the Mg level up 100 ppm. That’s a lot of liquid! More than a can of beer! I just can’t see dumping that much magnesium chloride in my tank all at once.

Randy’s numbers are more conservative, especially the low end of his suggested range. I think I’ll start there and see how it works out.

Again, thanks everyone, for all the replies.

 

[cybrook1421]

@Sailor I am in the same boat as you and reading your thread. Through all the other posts I have seen, everyone seems to agree that it takes a substantial amount of liquid to raise magnesium because it cannot be as concentrated as the alk of calcium. I do the BRS mag liquid and it states that 450ml will take my 80 gallon tank from 1280 to 1350. So, although it seems like a crazy amount, I think it is fine if multiple people on multiple places are saying the same thing for different brands of magnesium.

 

[Rmckoy]

Thanks for the tip, guys, but that doesn't really help at all. The reef calculators tell me how much of a given product to dose to get me from Point A to Point B, but then they all say "Do not dose all at once". I ALREADY KNOW THAT!

Perhaps I should rephrase my question: Instead of how much can I safely raise the ppm in a single dose, I should have asked how much of a change in parts per million of a given supplement can a stocked aquarium tolerate in a single day?

It is safe to increase total magnesium by ___ ppm in a single day.
It is safe to increase total calcium by ___ ppm in a single day.
It is safe to increase total alkalinity by ___ dKH in a single day.

Stable is what we all thrive for .
We don’t need to adjust or dose to bring numbers up besides daily consumption ( what corals use per day and between doses

a huge dose or jump in anything isn’t good

 

[FishTruck]

What Randy said... Going slow on the ALK is the one you need to worry about the most.

0.5 to 1dKH / daily -

.. and counter-intuitively, I have found it is most important to fix an ALK CRASH slowly. So, when you find out that your alk has dropped to, say 5.5 dKH that is when you need to restrain yourself most of all from a quick correction.

 

[jamesoconnor]

There are charts available everywhere that list ideal water parameters for any type of system (like a mixed reef, SPS dominant, natural seawater, etc.). But what is not at all clear is how much of any particular supplement you can safely add at any one time to bring your current water chemistry up to chart specifications.

For example, the labels Red Sea Foundation B and C clearly show that 1ml of supplement per 100 liters of water will raise the alkalinity by 0.1 dKH, or the magnesium by 1 ppm. Okay, fine. The label on the back goes a step further. It shows the total amount needed to bring your current level up to the desired level. Again, okay, fine! In my case, the last ICP test reported Mg at 1180 ppm, and since the target level in my mixed reef tank is 1350, the chart says I need 170 ml per 100L, or 680 ml in my 400L system.

Surely, they’re not telling me to dump the entire 500 ml bottle and half of another one into the tank at one time! That’s insane! So, how much is too much?

I’m not asking how much of any manufacturer’s product to add to any particular tank, but rather where do you draw the line for any particular parameter. In other words, how many parts per million can you safely raise the magnesium level in a single dose? How much dKH can you bump up safely in a single dose? Again, I’m not asking how many drops, or milliliters, or ounces of supplement to add. I’m asking how much of a change in solution (expressed in ppm or dKH) can the aquarium inhabitants tolerate when that change occurs instantaneously?

Dosing calculator

Calculate dosages for the balling method or adjustment of a single water parameters. Supports the most common additives for raising calcium, carbonate hardness and magnesium.

reefapp.net

 

[NormanB]

I used this calculator and input your data. https://reef.diesyst.com/chemcalc/chemcalc.html

The results and Usage/Warning are below.

Product required: 680 ml; 22.9 fl oz; 136 tsp

Warnings and usage: Warning: Shake well before use and add it to a high flow area, Dose 1/3 to 1/2 and the next day test. Check your levels and then dose another portion. Limit the increase to a Max. of 100 ppm/Day