Corals consume 1dkh a day...soda ash.

[Miami Reef]

Hello. My tank consumes 1dkh a day, and I dose soda ash manually once a day starting.

Am I doing alright? I know you aren't supposed to dose soda ash for large adjustments, but every day is a large adjustment. I think my PH rises to 8.4 max after dosing, but those API tests aren't the greatest.

I dose much less calcium than I do Alkalinity. Apparently it'd supposed to go at the same rate, but it's not.

Should I switch to sodium bicarbonate?

 

[Miami Reef]

Also. I’ve been testing calcium and Alkalinity every day and I consistently see calcium drop 5ppm and alk drops 1dkh every day.

My goal parameters are Cal 465 Alk 11

 

[Randy Holmes-Farley Verified Community Expert]

That is a pretty high alk target, but is fine if you elected it for faster hard coral growth. Be sure to maintain adequately high nutrients to avoid issues.

You are not really seeing unbalanced demand. At 1 dKH alk drop per day, calcium will only drop about 6.7 ppm per day, so your measurement of 5 ppm per day is as close as you can expect to be with a hobby kit.

It's ok to dose less than equal parts, but I personally would stick to equal parts (assuming it is designed for equal parts) until calcium got too high because calcium testing is not good enough for constant jiggering of doses.

What two part are you using? Not all are properly designed for 1:1 dosing, even when they claim to be.

 

[Miami Reef]

@Randy Holmes-Farley
These are the exact products I’m using.

According to the calculator, I need 210 ml of dissolved soda ash and 143ml of dissolved calcium chloride daily. I inputted that my alk is 10 and I wanted it at 11 and for calcium I put 460 and goal is 465

 

[Randy Holmes-Farley Verified Community Expert]

OK, so assuming you make a two part from them as my DIY directs (BRS uses my recipe), then it is appropriate to use 1:1 dosing unless you need to make substantial correction (up or down) to calcium.

 

[blasterman]

Personally I would drop your alk target to around 10 or so but its a personal preference.

I've rarely owned an SPS tank that consumes alk and calcium equally. It requires a lot of SPS to do this. Unfortunately market brain washing convinces people something is wrong if your alk consumption isn't just like a 1000 gallon 10 year old Acropora dominant tank. Its BS.

Moderate pH increases from soda ash or kalk dosing doesn't bother coral. Its pH decreases that bother coral.

My dosing pump is not trustworthy and I manually dose alk every night. My main SPS tank chews up 2-3 dKH per day depending on pH and growth is nutz. I then spike it back every night. Its the average over 24hours that matters.

Obviously I'm losing some potential growth given alk has fallen so much during the light cycle. I concede that. However I'm not racing somebody for growth. I want healthy control and not relying on wonky gear made in China.

Last, I've owned reef tanks for 30+ years and not seen a lick of difference running calcium over 400.

 

[Miami Reef]

OK, so assuming you make a two part from them as my DIY directs (BRS uses my recipe), then it is appropriate to use 1:1 dosing unless you need to make substantial correction (up or down) to calcium.

How do I know which amount to use? Because calculator says more of alk than cal.

Yes. I use your recipe

 

[Miami Reef]

Should I start at 200ml of each daily and test weekly to make adjustments?

 

[Randy Holmes-Farley Verified Community Expert]

How do I know which amount to use? Because calculator says more of alk than cal.

Yes. I use your recipe

Always dose a two part based on alk demand, and only slowly adjust the calcium up ir down over time as repeated tests indicate a better calcium value is needed.

That said, in your case, the doses are nearly identical for 1 dKH and 5 ppm calcium, so it really doesn't matter.

 

[blasterman]

What Randy said × 10^7

Its nice to have calcium dialed in perfectly for daily dosing, but its not life or death. Alk on the other hand needs to ideally be kept at a daily average. Alk just moves so fast in a healthy tank one or two days not being on it and its off by a lot.

I test calcium once a week and dose once a week to get back to 450. A lot more accurate that way than trying to split hairs daily when coral isn't going to care anyways as long as calcium > 400.