some advice on alkalinity

[docforestal]

Hello
Background: 55 gallon tank up almost 4 months - no fuge, HOB skimmer and filter for detritus; live rock, fish and plans on corals, sps
running higher phosphates and nitrates , getting better with chaeto reactor (no fuge) and skimming dialed in better
salt mix i have been using , first 100 gallon batch made salt with 1.025, alk 9.1, cal 500, mg 1350
i just recently found the 2nd batch i have been making has alk of 7.9 (might be my error) but s.g. still 1.025
so i think as i was doing water changes, my alk was dropping
once a week i am using calculator to add ~40-110 cc kalkwasser slowly (over an hour) to the tank to bring back up - plan on getting dosing pump and dial in my needs - theoretically should not be much eating it up unless it is settling out (and i am growing chaeto but that should not be a factor) - i do not see blooms of corralline everywhere either - a little here an dthere but is early

yesterday alk was 7.6, ph 8.0; dosed per calculator (on brs- as i have their kalk solution) 117cc over 60 min. 10 cc in high flow every 10 min.
today readings the same
last calcium checked was 2 weeks ago when alk was 7.9 and was 515 - have not checked mg for a while but can if helpful
phosphates yesterday down to lowest ever 0.05 and nitrates were 22 (down from 28 the week prior)

any thoughts? thanks

 

[Randy Holmes-Farley Verified Community Expert]

An alkalinity of 7.56 dKH is fine. Some would say perfect.

What size tank are we talking about?

 

[docforestal]

55 gallon- I guess my concern was the drop but perhaps it iscoming to a good homeostasis ?

 

[exnisstech]

I may be doing it wrong but I typically use two part to raise alk to the desired level then use kalk to maintain it tho it rarely does and I still need to dose a little two part. I have a system about 220g total that I drip kalk 24/7 45 minutes on 5 minutes off and I still have to dose 30ml of two part daily to keep alk around 8

 

[Spicy Reef]

What's the Mag in the tank? it's possible w/ low mag, the alk is precipitating..

For me those are the 3 pillars (alk, calc, mag), as long as I can keep each steady, all has been good. Of course there's plenty else that needs to be kept in line
Sounds like you're on top of things.

 

[docforestal]

I may be doing it wrong but I typically use two part to raise alk to the desired level then use kalk to maintain it tho it rarely does and I still need to dose a little two part. I have a system about 220g total that I drip kalk 24/7 45 minutes on 5 minutes off and I still have to dose 30ml of two part daily to keep alk around 8

thanks, i may need to change to doing 2-part

What's the Mag in the tank? it's possible w/ low mag, the alk is precipitating..

For me those are the 3 pillars (alk, calc, mag), as long as I can keep each steady, all has been good. Of course there's plenty else that needs to be kept in line
Sounds like you're on top of things.

i had not measured this in a while


sorry again for a wordy post:


so 2 days from above readings - was away -
new readings from several test kits
for what it's worth - red sea ca/alk/mg i could not discern pink to blue just light to dark purple on a continous spectrum and could not get a result - so it goes in the back closet

55 gallon tank - no fuge, hob skimmer and filter for water polishing - have small amount carbon (1/2 cup) changed monthly and had gfo but stopped using with chaeto reactor - now in 2nd week - chaeto stopped growing when po4 dropped

s.g. (refractometer) 1.026
Nitrate (hanna) 16.8 (best it's been - coincidentally my skimmer is producing more now)
pH (hanna) 8.3 (fluctuates depending on time of day 8.0-8.3 - i am waiting on a meter so i can track )
Ca (hanna) 505; reviewing other posts note hanna not felt to be as accurate on ca?
Ca (salifert) 390 (perhaps more likely ?)
Alk (hanna) 7.4
Alk (salifert) 7.3
PO4 (hanna) 0.05
Mg (Aqua Forest) 1095 (last checked with same kit March 4 - was 1350)

my last batch of salt thru the batch or user error may have been mixed weakly with the other components (b-ionic) - but I adjusted the alk to 9 in the salt mix with kalk and have done 3 water changes totalling 25 gallons in the last 2 weeks

so despite adding kalk (i have used 70ml of kalk liquid per 5 gallons fw top off - use ~3.5-4 gallons/week)
my reading of 7.6, i dosed slowly the tank with kalk per brs calculator and 24 hours later it remained at 7.6
now 2 days later it is 7.4

should i start dosing 2 part as calcium is perhaps actually low as well?
am i precipitating? other than the chaeto and a little macro/coralline - nothing should be eating it up (no corals)

thoughts/help appreciated - even if 7.4-7.6 is ok - for eventual sps growth in future i would like it stable and keep it from dropping, which it is steadily over the last month where it had been 8.7-9.1

 

[Spicy Reef]

thanks, i may need to change to doing 2-part

i had not measured this in a while


sorry again for a wordy post:


so 2 days from above readings - was away -
new readings from several test kits
for what it's worth - red sea ca/alk/mg i could not discern pink to blue just light to dark purple on a continous spectrum and could not get a result - so it goes in the back closet

55 gallon tank - no fuge, hob skimmer and filter for water polishing - have small amount carbon (1/2 cup) changed monthly and had gfo but stopped using with chaeto reactor - now in 2nd week - chaeto stopped growing when po4 dropped

s.g. (refractometer) 1.026
Nitrate (hanna) 16.8 (best it's been - coincidentally my skimmer is producing more now)
pH (hanna) 8.3 (fluctuates depending on time of day 8.0-8.3 - i am waiting on a meter so i can track )
Ca (hanna) 505; reviewing other posts note hanna not felt to be as accurate on ca?
Ca (salifert) 390 (perhaps more likely ?)
Alk (hanna) 7.4
Alk (salifert) 7.3
PO4 (hanna) 0.05
Mg (Aqua Forest) 1095 (last checked with same kit March 4 - was 1350)

my last batch of salt thru the batch or user error may have been mixed weakly with the other components (b-ionic) - but I adjusted the alk to 9 in the salt mix with kalk and have done 3 water changes totalling 25 gallons in the last 2 weeks

so despite adding kalk (i have used 70ml of kalk liquid per 5 gallons fw top off - use ~3.5-4 gallons/week)
my reading of 7.6, i dosed slowly the tank with kalk per brs calculator and 24 hours later it remained at 7.6
now 2 days later it is 7.4

should i start dosing 2 part as calcium is perhaps actually low as well?
am i precipitating? other than the chaeto and a little macro/coralline - nothing should be eating it up (no corals)

thoughts/help appreciated - even if 7.4-7.6 is ok - for eventual sps growth in future i would like it stable and keep it from dropping, which it is steadily over the last month where it had been 8.7-9.1

checked out ur build page, is that already cultured live rock with coralline algae already on it? Nice...
I think the coralline algae is the only think demanding alk and calcium at this point, or do you have corals that I missed?
so if it was me, my main focus would be getting the magnesium back up slowly of course. once it's up the alk should follow (w/ normal dosing) Randy has some nice writeups that got me through this... also if "soda ash"/sodium carbonate doesn't bring it up then try sodium bi-carbonate/baking soda.
I'd read up on it more than my grain of salt advice though get a good feel for it before implementing, you have the time nothing in your tank seems to hinge on haste here.

 

[docforestal]

hi @Spicy Reef - this is real reef rock, came that color - although i think it is getting a good coating of corraline - will try some close ups, as the colors and thickness is changing on most of the rock
appreciate the advice and will start bringing up the mag and figuring out the dosing