getting an autodoser for Christmas......questions

aslmx · Dec 17, 2012

75 gallon-going to dose -cal,alk,mag. what are some normal daily doses for a loaded 75 gallon and how do I need to go about finding my magic numbers, Ive been testing and coping down what ive been dosing and its not consistant, I hve to add 50ml one day and 150ml next day. any advice would help.

bkoppes · Dec 17, 2012

Should be the same each day.

KoleTang · Dec 17, 2012

Use the BulkReefSupply Reef Calculator.

You should not be dosing random amounts.

urbaneks · Dec 18, 2012

Step 1
Decide on your Alk, Cal and Mag targets. I will use my system as an example for you to follow; I like my Alk at 8, my Cal at 430 and my Mag at 1330.

Step 2
Test your tank for the parameters listed above. Use the calculator on the BRS site to determine how much of each component you need to dose to get to your targets. Dose that amount and retest ~30 minutes later to ensure you've hit your targets. If you need to make a second dose do so.

Step 3
Don't dose anything for the next 24 hours and then read your parameters again as close to 24 hours later from your first readings. Example.. in my initial readings I dosed my Alk to 8.1, when I tested the next day my Alk was at 7.0. In other words, my tank consumed 1.1 dKH of Alk in 24 hours. Again, I use the BRS site to calculate how much Alk I need to dose to get back to my target. In my case it was 86 mL, this now becomes your initial dose. Set both the Cal and Alk to dose 86 mL over the next 24 hours. At this point, I would let the doser dose 86 mL for 2-3 days before testing again. At the 2-3 day mark, I would test again and make an adjustment up or down as needed.

For Mag, you follow the same steps listed above, you will have a independent value from your Cal/Alk. My tank is mostly SPS, 110g of actual water. I dose 105 mL of Cal and Alk per day and 12 mL of Mag per day.

Words of wisdom here;
- Resist the urge to set a different number for Cal and Alk, dose the same amount and overtime you will end up in the correct balance. When I'm setting my doser up, I don't even test Cal again until I know my Alk is where I want it. Alk is the key, Cal will follow. When I first got a doser, I tried to tweak Cal and Alk separately and you just end up chasing numbers around.
- Don't chase a number, but instead have a range. For example, my Alk goal is 8.0 but if I get a reading between 7.5 and 8.5, I consider that good enough.

Once you've locked in your dose, you can go to weekly tests of Cal/Alk and Mag to to make sure that you tank demand is not going up or down.

Hope this helps.

Singlefin · Dec 18, 2012

Right now my tank consumes 1 dkh and 10ppm calcium a day (with kalk in my ato) which would be 90ml of alk and 46ml of calcium. Going by your theory, which may be correct, I would be dosing twice the calcium I need and would quickly put me over. Am I missing something? Sorry, not trying to be a wise *** or anything, just trying to figure this out because I'm about to start auto dosing in the next couple days. Which may make sense once I start, but still a little confused. Thanks for the help.

urbaneks · Dec 18, 2012

Singlefin said:
Right now my tank consumes 1 dkh and 10ppm calcium a day (with kalk in my ato) which would be 90ml of alk and 46ml of calcium. Going by your theory, which may be correct, I would be dosing twice the calcium I need and would quickly put me over. Am I missing something? Sorry, not trying to be a wise *** or anything, just trying to figure this out because I'm about to start auto dosing in the next couple days. Which may make sense once I start, but still a little confused. Thanks for the help.

I don't use kalk so I can't speak to how that is influencing your results.

The other thing that you need to state is what cal/alk values you are keeping your tank at and how large is your tank? These are important in the equation.

You could be trying to achieve a ratio that is not in ionic balance. I just ran the numbers for 110g and adding 1 dkh is about 90ml and 10 ppm is 112 ml. If you set up to dose 90ml you will get the alk you want with a bit lower cal but a better balance between the two.

Singlefin · Dec 18, 2012

Thanks. I might be stopping the kalk just to take one variable out of the equation. I have a 40b with a 20L sump. Total I have 45g of water volume. I'm using the BRS 2 part solution for calc. And alk. I hope I read the numbers right on the BRS calculator.

aslmx · Dec 18, 2012

urbaneks said:
Step 1
Decide on your Alk, Cal and Mag targets. I will use my system as an example for you to follow; I like my Alk at 8, my Cal at 430 and my Mag at 1330.

Step 2
Test your tank for the parameters listed above. Use the calculator on the BRS site to determine how much of each component you need to dose to get to your targets. Dose that amount and retest ~30 minutes later to ensure you've hit your targets. If you need to make a second dose do so.

Step 3
Don't dose anything for the next 24 hours and then read your parameters again as close to 24 hours later from your first readings. Example.. in my initial readings I dosed my Alk to 8.1, when I tested the next day my Alk was at 7.0. In other words, my tank consumed 1.1 dKH of Alk in 24 hours. Again, I use the BRS site to calculate how much Alk I need to dose to get back to my target. In my case it was 86 mL, this now becomes your initial dose. Set both the Cal and Alk to dose 86 mL over the next 24 hours. At this point, I would let the doser dose 86 mL for 2-3 days before testing again. At the 2-3 day mark, I would test again and make an adjustment up or down as needed.

For Mag, you follow the same steps listed above, you will have a independent value from your Cal/Alk. My tank is mostly SPS, 110g of actual water. I dose 105 mL of Cal and Alk per day and 12 mL of Mag per day.

Words of wisdom here;
- Resist the urge to set a different number for Cal and Alk, dose the same amount and overtime you will end up in the correct balance. When I'm setting my doser up, I don't even test Cal again until I know my Alk is where I want it. Alk is the key, Cal will follow. When I first got a doser, I tried to tweak Cal and Alk separately and you just end up chasing numbers around.
- Don't chase a number, but instead have a range. For example, my Alk goal is 8.0 but if I get a reading between 7.5 and 8.5, I consider that good enough.

Once you've locked in your dose, you can go to weekly tests of Cal/Alk and Mag to to make sure that you tank demand is not going up or down.

Hope this helps.

This sounds like a great formula to start. One question , do I need to ensure mag before I start with anything else?

Singlefin · Dec 18, 2012

fener103 · Dec 18, 2012

Plus one on getting the mag reading first as your Calcium will be slow to no go withour proper levels. I used the BRS calculator and there is a you tube vid as well. I did not start at their recommended value (tank is not that heavily stacked). Test where you are at to start with. Dose to the levels you want by hand. Double check your adjustments and turn on the dosers. Wait a day or two test again and adjust as necessary both manually and timer wise. I recommend checking at the same time of the day if time permits it. Enjoy

urbaneks · Dec 18, 2012

As it's been mentioned a couple times, it's best to get your Mag set where you want it at the same time you are dialing in Cal and Alk. Your mag will reduce much slower than the other 2 and your tank can tolerate much larger swings as you dose the tank back up. In other words, it's best to get mag set but I would not obsess over it.

aslmx · Dec 19, 2012

I did the 24 hour check and im losing 1 dkh on alk and around 20 ppm on cal. brs says 64 ml of alk and 184 ml calcium. i ll use this as my starting point when I get started.