Help trying to figure out daily dosing numbers

[eagle14489]

Hello All.

1st of all thank you for helping me with your knowledge on this post.

So let me start off with I am running an Innovative Marine Sr-80 with mainly SPS corals with several torches, zoas, and so on. ( see photo) I am running a Jabeo doser 3.4 (wifi). Using BRS Alk mixed in a gal at a time. I am using Reef Crystals with RODI water. My Cal is always very high local store tested it yesterday at 480, Alk at 8dkh, Mag at 1260, and point of sale at .05. I added Cheato to my tank as of yesterday because of the point of sale. I use Hanna checkers with new regents, not expired ones. I do water changes around every 3 weeks, Filter socks are changed every 3 days. tank is around 8-9 months old.

Right now I have my Alk dosing at 26ml daily. Below I am going to list all my tests with dates and what I dosed that day. I am trying to figure out what my tank is using so I can set it and hopefully not have manually adjusted it daily.

Alk (target 8.5)
Date Tested added
1/5 8.288 9ml
1/6 8.176 13ml
1/9 7.896 26ml
1/10 8.064 18ml
1/11 8.4 4ml
1/12 8.344 6ml
1/13 8.064 18ml (started auto dosing 5ml this day)
1/16 7.869 26ml
1/17 8.008 21ml (upped auto dosing to 10ml)
1/18 8.064 19ml
1/19 8.176 14ml (upped auto dosing to 15ml)
1/20 8.4 4ml (upped to 20ml)
1/21 8.176 14ml (upped to 22ml
1/22 7.952 24ml (upped to 25ml)
1/23 8.68 0ml
1/26 8.232 12ml
water change turned doser off as I thought the water change would adjust water readings.
2/4 7.336 50ml (doser turned back on at 20ml)
2/5 7.56 40ml (upped to 25ml)
2/6 8 (store tested) 0 added minus daily of 25ml
2/7 7.784 30ml (Upped to 30ml)


Mag
Date tested added
11/30 1300
1/5 1235
1/20 1205 100ml (over 24hrs) auto dosing
1/21 1220 "
1/22 1225 "
1/23 1265 "
1/26 1320 "
1/28 1355 0
water change
2/4 1490 0
2/6 1260
2/7 1280 (starting dosing 100ml daily again)

 

[jsker]

Wow, nice looking tank!!

 

[Randy Holmes-Farley]

Don't bother measuring magnesium more than once a week or less. It moves far too slowly to see changes on a daily basis. Real magnesium demand is 1/10th or less of the calcium demand and is rarely over about 1 ppm per day.

Instedd of trying to change the dose every day, I'd dose 20 mL of the alk per day for a week and see how the alk changes. Measuring and changing doses too frequently leads test errors to drive the answers too much. Then after a week make a correction if needed, and repeat the week test. Every alk reading you posted is perfectly fine, so there's no need for constant adjustment.