alkalinity and calcium questions

aussiejohnny

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im struggling a bit with dosing calcium and alkalinity ..followed directions for calcium and ended up not dosing enough and when tested at my lfs i got 324 as my reading
with alkalinity i thought id worked out my dose and ended up with a dkh of 13.5 ...monitoring my alk with a hanna checker which i think is measuring 1 dkh more than is correct i have allowed the tank to naturally use the alk and im getting a usage of 1 dkh a day which would equal approx 5 ml of reef fusion a day which is what i was dosing originally ..only difference in stocking now to then is 5 snails which have tripled there size in a month and 2 hammer frags of decent size ..could they now be consuming that amount of dkh and the reason my calcium mag dropped so quickly where those 2 elements barely changed over that period..the tank is looking good no loses i wonder if im actually working out the volume of water in the tank correctly maybe im under estimating amount of water ..430 cm wide 410 cm high 380 cm wide including built in sump ..i got 67 liters is that correct?..other parameters are ok nitrate 1 phos .01 1.026 salinity ..
 

Subsea

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im struggling a bit with dosing calcium and alkalinity ..followed directions for calcium and ended up not dosing enough and when tested at my lfs i got 324 as my reading
with alkalinity i thought id worked out my dose and ended up with a dkh of 13.5 ...monitoring my alk with a hanna checker which i think is measuring 1 dkh more than is correct i have allowed the tank to naturally use the alk and im getting a usage of 1 dkh a day which would equal approx 5 ml of reef fusion a day which is what i was dosing originally ..only difference in stocking now to then is 5 snails which have tripled there size in a month and 2 hammer frags of decent size ..could they now be consuming that amount of dkh and the reason my calcium mag dropped so quickly where those 2 elements barely changed over that period..the tank is looking good no loses i wonder if im actually working out the volume of water in the tank correctly maybe im under estimating amount of water ..430 cm wide 410 cm high 380 cm wide including built in sump ..i got 67 liters is that correct?..other parameters are ok nitrate 1 phos .01 1.026 salinity ..
Consider posting in reef chemistry forum. 1ppm of nitrate is not OK. Get it above 5ppm. @Randy Holmes-Farley recommends 10-50ppm of nitrate.
 
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Randy Holmes-Farley

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what are you using to measure calcium?

I’d stop measuring magnesium at all. I don’t consider home testing to be accurate enough to guide dosing. Just dose magnesium in proportion to calcium dosed.
 

Randy Holmes-Farley

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This has more on magnesium

 
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A

aussiejohnny

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what are you using to measure calcium?

I’d stop measuring magnesium at all. I don’t consider home testing to be accurate enough to guide dosing. Just dose magnesium in proportion to calcium dosed.
local fish store i get my water tested every 2 weeks...dont have a calcium test kit ..been cutting back with carbon dosing all the way to 1 ml a day ..got a 1ppm nitrate but its back to 0 again ..
 

Reefing addict Clay

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All your coral seem happy and looking great so that’s awesome but yes Crystal clear water makes for better viewing
 

Randy Holmes-Farley

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local fish store i get my water tested every 2 weeks...dont have a calcium test kit ..been cutting back with carbon dosing all the way to 1 ml a day ..got a 1ppm nitrate but its back to 0 again ..

My suggestion is to get your own alk and calcium testing (if you want to dose them separately) or just alkalinity if you use a combo product.

I would not assume the lfs calcium test is accurate and you have no easy way to go about checking it. At home you can check the new salt water and track changes more readily.
 

SonOfaGoat

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Could the alk dose be causing calcium precipitation? Im new to dosing myself and am using All For Reef, but my Alk was low so I dosed some Reef Buffer. ( I realize now its maybe not the best product ) but overdosing can cause cal and mag consumption if im not mistaken.
 
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aussiejohnny

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thanks everyone for advise ..ive now realized i wasnt doing the reef fusion dosing correctly ..actually 5 ml a day is a dble does of alkalinity ..and i only dosed half of that amount calcium and after adding snails and some coral i guess calcium got used but because my alk dose was high i didnt realize they were out of wack till i got calcium tested ..next trip to lfs ill do a alk test on my hanna and compare to theres to see if my hanna is reading right or not...everything looks great actually and the snails have grown and laid eggs all over the glass ..this my second attempt with corals and i guess im overcompensating as i had issues with phosphate and didnt even realize how important dkh and calcium were ..had aquariums all my life and still learning at 65 yrs old..
 

Randy Holmes-Farley

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Could the alk dose be causing calcium precipitation? Im new to dosing myself and am using All For Reef, but my Alk was low so I dosed some Reef Buffer. ( I realize now its maybe not the best product ) but overdosing can cause cal and mag consumption if im not mistaken.

Yes, alk and pH too high can accelerate precipitation.
 

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