How do I figure out daily dosing levels?

[mje113]

This question applies broadly as I've been needing to dose NO3 and PO for a while to keep those levels detectible, however the specific example I'll use is Alkalinity, as I just started testing this week.

I tested Alk for the first time and got 7dKH, so I figured I would use my Red Sea Foundation Alkalinity to bring that number up a bit. the Red Sea calculator said I should be adding 4.5ml daily, but since this was the first time using I added 2ml. Tested the next day and it was still 7.

So, I then added the recommended 4.5ml and tested the following day and I'm at 8.4dKH. Sounds like a good spot. The question I have is do I keep dosing the same amount daily? I'd like to get to a point where I know how much to dose daily, but also with only having to test weekly. I'm sure there's some methodology to figuring this out but I'm stumped.

 

[Jekyl]

Test using reliable tests over the course of a few days until you can find the trend of daily consumption. Once you know the number use a calculator like this one

Reef Chemistry Calculator

 

[Biglew11]

1. Get your levels where they need to be.
2. Test 3-4 days later.
3. Get them back to where you want them.
4. Divide the amount you had to dose by the number of days you waited. This number will be what you need to dose per day.
5. This works with anything you want to dose.

 

[melbournedan]

1. Get your levels where they need to be.
2. Test 3-4 days later.
3. Get them back to where you want them.
4. Divide the amount you had to dose by the number of days you waited. This number will be what you need to dose per day.
5. This works with anything you want to dose.

how do i bring up my alk from 2.5 (redsea test) back upto normal numbers without shocking the system ?

 

[Dburr1014]

how do i bring up my alk from 2.5 (redsea test) back upto normal numbers without shocking the system ?

It's the same concept, almost.
Do you know how much you need?
You can raise the dkh by 1 daily.
Add some, test a few hours later, how much of a rise? Once you know how much of a rise per dose, you can gauge how much you need daily to bring it up to 8ish dkh.

 

[melbournedan]

It's the same concept, almost.
Do you know how much you need?
You can raise the dkh by 1 daily.
Add some, test a few hours later, how much of a rise? Once you know how much of a rise per dose, you can gauge how much you need daily to bring it up to 8ish dkh.

i’m using red sea foundation B, so 1ml should raise the alk in my 15gal .2 dkh. i’ve added 4ml. (0.8dkh) and will test and dose another 4ml until i reach 8dkh, raising .8dkh/per day, not taking into account the intake from corals.

 

[LeftyReefer]

There are a number of ways to do it, as mentioned above.

The idea is to figure out how much ALK your tank consumes over a given time, and replace (dose) that amount back over the same time to keep the ALK consistent.

so you can test your ALK, then not dose anything.... wait a week, then test again. then you will know how much ALK your tank consumed in a week. Then just dose that amount over a week and see if ALK stays stable. if not, tweak your dosage a little at a time until you get it where it needs to be.

Also keep in mind that ALK consumption can change throughout the day. so it helps if you can test at the same time each day to take any hour to hour consumption changes out of the equation.

For example, do your first test on a monday at 8pm. Do your next test the following monday at 8pm. then you will know how much your tank consumed in a week. Dose your tank back up to your target and then start dosing that amount over the next week. Test again the following monday at 8pm and see if ALK stayed at/near your target. if not, tweak your dosages a bit to get it closer.

 

[Rmckoy]

7 isn’t a bad place to be for dkh
Nsw is around 7-7.5
To calculate consumption bring the levels up to your target and test for 5 days not dosing .
after 5 days use the calculator and divide it by 5
That will be your daily amount .
Depending on what salt you’re using
water changes were always said to be easiest to maintain levels in a newer system with little demand

 

[melbournedan]

There are a number of ways to do it, as mentioned above.

The idea is to figure out how much ALK your tank consumes over a given time, and replace (dose) that amount back over the same time to keep the ALK consistent.

so you can test your ALK, then not dose anything.... wait a week, then test again. then you will know how much ALK your tank consumed in a week. Then just dose that amount over a week and see if ALK stays stable. if not, tweak your dosage a little at a time until you get it where it needs to be.

Also keep in mind that ALK consumption can change throughout the day. so it helps if you can test at the same time each day to take any hour to hour consumption changes out of the equation.

For example, do your first test on a monday at 8pm. Do your next test the following monday at 8pm. then you will know how much your tank consumed in a week. Dose your tank back up to your target and then start dosing that amount over the next week. Test again the following monday at 8pm and see if ALK stayed at/near your target. if not, tweak your dosages a bit to get it closer.

i’m more concerned about raising it too quickly. i’m thinking i’ll use this first week to get it slowly back into reasonable numbers and next week work out consumption.

 

[Biglew11]

i’m more concerned about raising it too quickly. i’m thinking i’ll use this first week to get it slowly back into reasonable numbers and next week work out consumption.

About 1dkh per day.

 

[Randy Holmes-Farley Verified Community Expert]

how do i bring up my alk from 2.5 (redsea test) back upto normal numbers without shocking the system ?

2.5 meq/L?

Surely you are not thinking the tank water is 2.5 dKH?

 

[melbournedan]

2.5 meq/L?

Surely you are not thinking the tank water is 2.5 dKH?

no definitely 2.5dkh, which is why i’m concerned about raising it quickly. using red sea alk test kit, only 5 drops is producing the test end color.

 

[Garf]

no definitely 2.5dkh, which is why i’m concerned about raising it quickly. using red sea alk test kit, only 5 drops is producing the test end color.

You tried testing new saltwater with the same test kit?

 

[Randy Holmes-Farley Verified Community Expert]

no definitely 2.5dkh, which is why i’m concerned about raising it quickly. using red sea alk test kit, only 5 drops is producing the test end color.

That’s not likely an accurate measurement, so don’t raise it at all before testing with another kit and/or checking a standard.

 

[AFHokie]

no definitely 2.5dkh, which is why i’m concerned about raising it quickly. using red sea alk test kit, only 5 drops is producing the test end color.

Does this tank have inhabitants?

 

[melbournedan]

Does this tank have inhabitants?

 

[melbournedan]

That’s not likely an accurate measurement, so don’t raise it at all before testing with another kit and/or checking a standard.

dang. i honestly didn’t even think that it could be wrong. i tested twice but got the same result. will do a test on some newly mixed red sea blue bucket tonight.

 

[melbournedan]

You tried testing new saltwater with the same test kit?

i will test some newly mixed red sea blue bucket tonight, i didn’t even think to test it against newly mixed because i double checked the tank and got the same result both times.

 

[zen]

i will test some newly mixed red sea blue bucket tonight, i didn’t even think to test it against newly mixed because i double checked the tank and got the same result both times.

My advice is to take a sample to your LFS and have them test your Alk for you before you go crazy with dosing. The worst thing you can do is start changing your parameters drastically. Your coral look good in the picture and that leads me to believe your test results are off.

 

[AFHokie]

Whoa. That tank looks oddly clean. How old is it? There’s barely a spec of anything anywhere.

I’m not a chemist by any stretch, and I’m sure Dr. Holmes-Farley will correct me if I’m wrong, but I don’t think it could be possible to have your saltwater at 2.5 dKH with anything alive….or if it’s chemically possible to have a proper SG and alkalinity that low.

The worst batch of salt I’ve had still mixed to 6 dKH at 1.025.