chemistry questions: mg test kits & calcium

docforestal · Mar 4, 2023

Morning
Tank has been setup 8-9 weeks or so, using b-ionic salt, doing 10-20 gallon water changes a week. I have 3 banghais, 2 small clown gobies, a filefish and a small faerie wrasse, added a week apart to get the tank cycled gently (was fully cycle prior)

s.g. stable 1.025-1.026 (using refractometer-recalibrated this am - no change)
pH stable 8.2 (api & probe)
Alk:(Hanna) 2/18 7.6 (dosed kalk ) 2/19 8.2, 2/23 9.7, 2/25 9.2, 2/27 9.2, 3/4 9.9
ca: (Hanna) 2/18 504 , 2/19 464 2/23 451, 2/25 480, 2/27 283, 3/4 500
Mg: 1/29 960 using red sea so i dosed per the calculator, 2/19 1560 (red sea-ordered aquaforest), 3/4 1320 with Aquaforest and >1600 with red sea
PO4: 2/18 0.06, 2/25 0.08, 3/4 0.22
Nitrates: 20 with hanna and api - over the last 2 weeks and go to 10 after a water change - working on dialing in my fish feeding amounts - i am skimming as well as small hob fuge with macro (wont do much i know)
as far as Mg - i am thinking the aquaforest is more accurate (what i have read), if not next steps other than water changes (doing routine one now)

Foolishly I just measured my salt mix (i think this is why my numbers have gone up)
with Hanna alk 9.8 and Ca 507, s.g 1.026, temp 74
as far as ca/alk - should I be concerned? change salt mix? I am mixing a 30 gallon batch at a time in a 32 gallon bucket (have measured using 5 gallon buckets to make sure my volume estimate is right), per the instructions with the 4 parts, salt, mg and the two bottles that do not label specifics.

thanks for any advice

wculver · Mar 4, 2023

docforestal said:
Morning
Tank has been setup 8-9 weeks or so, using b-ionic salt, doing 10-20 gallon water changes a week. I have 3 banghais, 2 small clown gobies, a filefish and a small faerie wrasse, added a week apart to get the tank cycled gently (was fully cycle prior)

s.g. stable 1.025-1.026 (using refractometer-recalibrated this am - no change)
pH stable 8.2 (api & probe)
Alk:(Hanna) 2/18 7.6 (dosed kalk ) 2/19 8.2, 2/23 9.7, 2/25 9.2, 2/27 9.2, 3/4 9.9
ca: (Hanna) 2/18 504 , 2/19 464 2/23 451, 2/25 480, 2/27 283, 3/4 500
Mg: 1/29 960 using red sea so i dosed per the calculator, 2/19 1560 (red sea-ordered aquaforest), 3/4 1320 with Aquaforest and >1600 with red sea
PO4: 2/18 0.06, 2/25 0.08, 3/4 0.22
Nitrates: 20 with hanna and api - over the last 2 weeks and go to 10 after a water change - working on dialing in my fish feeding amounts - i am skimming as well as small hob fuge with macro (wont do much i know)
as far as Mg - i am thinking the aquaforest is more accurate (what i have read), if not next steps other than water changes (doing routine one now)

Foolishly I just measured my salt mix (i think this is why my numbers have gone up)
with Hanna alk 9.8 and Ca 507, s.g 1.026, temp 74
as far as ca/alk - should I be concerned? change salt mix? I am mixing a 30 gallon batch at a time in a 32 gallon bucket (have measured using 5 gallon buckets to make sure my volume estimate is right), per the instructions with the 4 parts, salt, mg and the two bottles that do not label specifics.

thanks for any advice

I'll preface my answer by saying ionic balance is important so make sure to settle on a vendor for dosing.

That said, I use aquaforest and has been good for me. Your ca/mg looks good actually but need to get it stable. What I would say is if you stay with aquaforest is to get the alk in the 9.0 neighborhood and not in the 10.0 where it appears to be.

One tip also for me I measure everything on an electronic scale both salt and additives. This would get you away from the volume measurement at 5 gallons at a time and be less prone to error I think.

docforestal · Mar 4, 2023

i guess the issue with b-ionic is a 4 part mixture, that does not allow easy tinkering - why i think i may switch brands to a salt that allows me to then supplement as needed.
other than consumption, (just starting to get speckles of coralline and it will be quite a while before i put any corals in), i do not know how to decrease the alk/ca other than water changes with another salt

thoughts?

my plan if it sounds reasonable is to get marine mix salt which gives alk 9.0, ca 445-450 and mg 1350

at this point i do not want to put funds to probes for each reading, just rather use test kits that are reliable/consistent - for now i am assuming red sea is off/bad batch( i have done the test several times, same results so do not think is user error - although you never know- been a while since college chemistry )