How to determine proper dosing amounts?

[Capsle]

Hey reefers,

So I am reading into dosing for Ca, Alk and Mg. I've been dosing Mg every other day to get it to where I wanted, 1385. Its is steady and stable. For Ca and Alk I have been relying on WC to get parameters back up as my tank hasn't been using a lot. Maybe 10-30 ppm of Ca per 2 weeks and 07 Kh (9.3 down to 8.6 ish).

I've read that is better to dose daily in smaller amounts than less often in bigger amounts. So my question is how do I go about figuring out how much to dose daily.

I'm new to this part of the hobby so any insight or experienced input would be greatly appreciated.

Thanks in Advance.

Caps

[Sk8r]

Don't your elements come with instructions printed on the container? These are given in units per gallon of system water. It's ok to estimate a little less because of the rock and sand, but it's also that that critical a measure.

[Capsle]

Yes, the chemicals do come with instructions lol.

I meant for the amount of daily dosing. Do I measure my tank everyday for a month so see what the levels drop by and then average it out?

[scooter31707]

I get my levels where I want them and I measure again in 3 days and subtract the regular number from the 3 day number divided by 3 days.
For example with Ca:

Achieved level: 3 Day Test: Dosing Measurement:
450-420/3=10ml

Hope that helps

[ryeguyy84]

I just adjusted my dosing after a semi crash so it's fresh in my mind. What I did was tested my levels and got mag in line at 1400. Then once that was good I tested everything again and turned off my dosing pumps. In my case alk 7.78/cal 410/mag 1400. Then I waited 5 days and tested again and got alk 6.72/cal 400/mag 1400. Figured out what it took to get alk back up with the brs calculator and divided by 5 to get the daily dose. Then dosed that amount of alk and cal for a week and made minor adjustments.

[hkgar]

I use this to determine how much to dose.

http://reef.diesyst.com/chemcalc/chemcalc.html

I use this to calculate system water:

http://reef.diesyst.com/volcalc/volcalc.html

Not sure if this is what you are looking for, but I hope it helps. To spread out dosing during the day you might want to look at some low volume peristaltic pumps. When I dosed two part I used the BRS 1.1 ml/minute pumps. You will need a way to control them.

[Sk8r]

I prefer to stabilize my levels at 1350 mg, alk 8.3 dkh, cal 420: once I have all three of those set, I add kalk to my ato and don't have to worry about checking anything but mg once a week, because kalk will continue to hold those levels steady. Or you can check alk, which is a faster, less fussy test.

If alk is falling it means so has your mg, and it fell first, so check it, correct it, then correct your alk (and probably your cal) and then you're good until next time the tank mg level falls below 1200.

It's a kind of magic, but it doesn't take a doser (unless you count the ato) and it works.

[ssick92]

Yes, the chemicals do come with instructions lol.

I meant for the amount of daily dosing. Do I measure my tank everyday for a month so see what the levels drop by and then average it out?

Basically this. Doesn't necessarily need to be for a month, but you can figure how much it drops every day, or every 2 days, and dose just enough to replenish that amount.

Use the instructions to give you an idea of how much to dose, and then you can use your testing to determine the exact amounts.

[GimpyFin]

For me, one thing I've found that helps is using a salt that has slightly buffered parameters from what I want to maintain. It keeps me ahead of the curve a little easier.

The salt I use is Kent which @ 1.025 yields calcium a little over 500, mag around 1400, and alk about 8.5. I do about 25% water change every 2-3 weeks, so the only thing I usually have to maintain in between is alk, which doesn't take much since I keep it consistently between 7-8. Obviously, what's in your tank comes into play as well, but the other two params stay within range for me. I still do periodic tests for cal and mag just to check, but it helps in the fact that I don't have to focus much on dosing outside of water changes.

[Capsle]

Awesome everyone, exactly the info I was looking for just stated in different way!

Thanks a bunch!


Sent from my iPhone using Tapatalk

[Sk8r]

Lol, Capsle, wasn't a snark: sometimes stores sell small jars from bulk, and they don't have labels. ;) Good you have the info.

[Breadman03]

Don't forget, close is fine. You don't have to hit an exact number. Get a decent ballpark and adjust slightly as needed. If something seems funny, stop and ask. :)

[gone fishin]

Don't forget, close is fine. You don't have to hit an exact number. Get a decent ballpark and adjust slightly as needed. If something seems funny, stop and ask. :)

My thoughts as well, consistency is more important than exact numbers.

[Jah2707]

I prefer to stabilize my levels at 1350 mg, alk 8.3 dkh, cal 420: once I have all three of those set, I add kalk to my ato and don't have to worry about checking anything but mg once a week, because kalk will continue to hold those levels steady. Or you can check alk, which is a faster, less fussy test.

If alk is falling it means so has your mg, and it fell first, so check it, correct it, then correct your alk (and probably your cal) and then you're good until next time the tank mg level falls below 1200.

It's a kind of magic, but it doesn't take a doser (unless you count the ato) and it works.

This is what I attempt to do as well.

[Nick30G]

So basically you need to get those ca, alk, and mg levels up to the correct levels and then you can maintain those levels by adding some kalk to your ato if im understanding correctly. I'm going to be building a 30g tank soon and will be having lps and soft corals and maybe sps corals. Would I have to dose and test for those 3 levels if I just have lps and soft corals? Or could I just do water changes? So this helps me understand a bit on how you maintain those important levels for corals.

[Sk8r]

Exactly. Kalk is calcium hydroxide or some such (I are NO chemist!) which, dripped into the tank in fresh water solution, maintains the calcium and the alkalinity nicely where it was. It's not good at raising either, but it won't let it fall, as it constantly dissolves and makes part of the salt water chemistry. The governing factor is the magnesium level: if that is under 1200, it cannot maintain. So as long as you keep your mg over 1200 (1350 is the common figure people shoot for) and keep 2 tsp per gallon of kalk in the ro/di topoff water, the readings will stay rock solid where you have set them. It's somewhat how the ocean does it. And it works nicely in our tanks with no special equipment except an autotopoff and a teaspoon.

[JMorris271]

and keep 2 tsp per gallon of kalk in the ro/di topoff water, the readings will stay rock solid
Are you adding the 2 tsp. of kalk to the container of the water you are going to add to the TO reservoir ?
Sorry to use your thread to ask this question.

[Capsle]

Exactly. Kalk is calcium hydroxide or some such (I are NO chemist!) which, dripped into the tank in fresh water solution, maintains the calcium and the alkalinity nicely where it was. It's not good at raising either, but it won't let it fall, as it constantly dissolves and makes part of the salt water chemistry. The governing factor is the magnesium level: if that is under 1200, it cannot maintain. So as long as you keep your mg over 1200 (1350 is the common figure people shoot for) and keep 2 tsp per gallon of kalk in the ro/di topoff water, the readings will stay rock solid where you have set them. It's somewhat how the ocean does it. And it works nicely in our tanks with no special equipment except an autotopoff and a teaspoon.

That's awesome info as I don't necessarily want to dish out 300$ for a dosing pump at the moment.


My parameters are set pretty good now and just want to maintain them. I don't mind manually dosing Mg as I do it right now (well was to bring it to where I wanted). If all I need is Kalk to keep Alk and Ca even I am good with that.

The 2 tsp per gallon of water, is that system volume or Top Off volume?
I am assuming system.

Sk8 I love how you seem to make everything so simple!

As always thank you everyone for your input.

[madweazl]

That would be to your gallon of top off water. You typically dont want to go over 1 KH per day so start slow and keep an eye on it for the first few days.