New tank Alk sink?

[ScottF]

Hello reefers! I have a new 250gal (total water volume) tank with no fish or inverts in it yet. It's been up for maybe a month. I used dry marco rock for my scape. I am trying to maintain an alk of 9dkh.

I realize that I don't have corals and the alk could be lower, but I do have a lot of CO2 in my house and would like to stabilize pH as much as possible while providing a good environment to promote coraline growth.

Every day the alk drops to around 8dkh and I add 1tbsp of baking soda dissolved in one quart of water to the tank which brings it back up to about 9dkh. I have soda ash on order from BRS and am planning on dosing it with one of my Neptune Dos heads when it gets here to maintain 9dkh.

I'm guessing that the alk is precipitating out. My calcium and magnesium are stable around 485 and 1336. Is this precipitation normal in new tanks? Will it eventually stop precipitating? Is there any reason (other than time, money and effort) not to keep my dkh pegged at 9 this early in the game?

Also,

I am currently using TM Pro Reef which mixes to around 7dkh. I wanted to use Nyos Pure Salt, but can't find any in stock anywhere. Should I be adjust the dkh in the mixing tank before my daily automatic 2% water changes happen or just dose a little extra part b to the tank? It seems like it would be easier to keep dosing consistent by just leaving the holding tank at 7dkh and dosing what part b is required to maintain 9dkh to offset the water changes. Then adjust the dkh in the holding tank if I need to do a large water change.

 

[00W]

Here's my advice.
Sit back, relax and chill a bit.
Tank is only a month old and started with dry rock.
You will be going through many stages in this tank and you are going to need to be patient.
I only tested salinity in my tank for the first 3 years.
Now
Is the tank cycled?
I would add some fish and clean up crew.
Feed. 250 gallons is a great size and water volume.
Stop changing water every day.
Let your tank grow, age, ripen. Become a little more diverse.
Then start testing.
You can test alk all you want but I wouldn't add corals for a few months anyway.
When you think you are ready, start getting your numbers in line with whatever you think they should be.
9 times out of 10 your tank will work itself out on it's own with only a small amount of help from yourself.
I've seen more tanks fail due to the owner than anything else.
Install a skimmer. Aeration is awesome!
Helps in all kinds of ways!
You'll get there I promise!
Lots of people want THAT tank right now but be patient.
My 2 cents only here, just trying to help and there's lots of other ways to go about it but I'm a slow and steady kind of guy.

 

[ScottF]

This is all very good advice. I had a reef tank before, but I've been out of the game for a decade. I'm just getting back into reefing again now. Before when I built my tank I cobbled it together piece by piece as it grew.

This time around I've decided to build it out with all of the bells and whistles from the get go. It has a Trident and TridentNP. So it's going to test parameters every day regardless. It has an Apex Controller and DosQD pumps so why not use them?

I agree that I need to try very very hard not to meddle and tinker too much with the tank, but it already has all of this automation built into it. I would like to get it dialed in as much as possible and keep everything as stable as possible from the get go unless there is a reason not too.

Is there any negative effects of having alk precipitate out like this? If so, that is a good reason for me to back off of the bicarb dosing. If not, I'd like to get the hang of managing all of this now and getting it dialed in before I have a tank full of corals that I could kill by overdosing additives.

I'm not trying to be snarky or anything. I do truly appreciate your very good advice. I just feel like now is the time to play with my toys and get a firm grasp on it all before I have an ecosystem depending on me.

I've got the skimmer. Plenty of aeration. We are good there. Plenty of surface agitation as well. No corals going in for a while. I do have some fish coming in the next couple of weeks.

 

[Jekyl]

Until you have corals the alk isn't a concern. As mentioned above you could save yourself some testing materials and just wait. The maturing of a tank never stops. The first year though is the worst and everything tends to go haywire. Best advice is to ride the wave and don't chase numbers as long as they are in acceptable ranges.

 

[knockout]

Here's my advice.
Sit back, relax and chill a bit.
Tank is only a month old and started with dry rock.
You will be going through many stages in this tank and you are going to need to be patient.
I only tested salinity in my tank for the first 3 years.
Now
Is the tank cycled?
I would add some fish and clean up crew.
Feed. 250 gallons is a great size and water volume.
Stop changing water every day.
Let your tank grow, age, ripen. Become a little more diverse.
Then start testing.
You can test alk all you want but I wouldn't add corals for a few months anyway.
When you think you are ready, start getting your numbers in line with whatever you think they should be.
9 times out of 10 your tank will work itself out on it's own with only a small amount of help from yourself.
I've seen more tanks fail due to the owner than anything else.
Install a skimmer. Aeration is awesome!
Helps in all kinds of ways!
You'll get there I promise!
Lots of people want THAT tank right now but be patient.
My 2 cents only here, just trying to help and there's lots of other ways to go about it but I'm a slow and steady kind of guy.

This is wonderful advise, new tank with no corals, you're burning a hole testing elements that at the moment have no play in the health of your tank, add a few fish and enjoy your glass-box/water-cage

 

[Randy Holmes-Farley]

I personally would not let alk drop below 7 dKH, because even without corals, it will be desirable to get coralline growing on rocks and thus deter algae and dinos from tanking those spots.

Alkalinity and calcium can deplete in new aquaria for several reasons, including deposition of calcium carbonate into bare calcium carbonate surfaces. Rising nitrate also depletes alk.

 

[ScottF]

I personally would not let alk drop below 7 dKH, because even without corals, it will be desirable to get coralline growing on rocks and thus deter algae and dinos from tanking those spots.

Alkalinity and calcium can deplete in new aquaria for several reasons, including deposition of calcium carbonate into bare calcium carbonate surfaces. Rising nitrate also depletes alk.

Thank you very much Randy. That is one of the reasons that I a trying to keep my dhK up despite not having corals yet. I seem to have a lot of CO2 in my house. So I am trying to stabilize pH as much as possible. I am also trying to provide an environment to encourage coralline algae growth. I also want to get a firm grasp of dosing before I have a tank full of fish and corals.

It's not a big deal right now if I misconfigure my dosing pumps and overdose sodium carbonate. Nothing but pods, algae and bacteria in the tank.

The calcium doesn't really seem to be depleting. Mostly just the alk. Does it mean that it's not deposition of calcium carbonate or is it just that calcium depletes way more slowly then alk.

It's not a big deal as long as continuing to dose carbonate to the tank isn't harmful in any way, but I would like to understand what is going on if possible. Half of the fun of owning a reef is learning new things.

Edit:
I should also mention that my dkH was indeed dropping well below 7 before I started dosing it back up to 9.

 

[Randy Holmes-Farley]

Thank you very much Randy. That is one of the reasons that I a trying to keep my dhK up despite not having corals yet. I seem to have a lot of CO2 in my house. So I am trying to stabilize pH as much as possible. I am also trying to provide an environment to encourage coralline algae growth. I also want to get a firm grasp of dosing before I have a tank full of fish and corals.

It's not a big deal right now if I misconfigure my dosing pumps and overdose sodium carbonate. Nothing but pods, algae and bacteria in the tank.

The calcium doesn't really seem to be depleting. Mostly just the alk. Does it mean that it's not deposition of calcium carbonate or is it just that calcium depletes way more slowly then alk.

It's not a big deal as long as continuing to dose carbonate to the tank isn't harmful in any way, but I would like to understand what is going on if possible. Half of the fun of owning a reef is learning new things.

Edit:
I should also mention that my dkH was indeed dropping well below 7 before I started dosing it back up to 9.

How much alk? One can deplete a couple of dKH of alk without really noticing the calcium consumption even when depositing calcium carbonate. There is way more calcium in seawater than alk, so a 10% change in alk (say, 0.7 dKH) is noticeable while the corresponding change in calcium (5 ppm or 1.1% of the calcium) is not easily detected.

 

[ScottF]

How much alk? One can deplete a couple of dKH of alk without really noticing the calcium consumption even when depositing calcium carbonate. There is way more calcium in seawater than alk, so a 10% change in alk (say, 0.7 dKH) is noticeable while the corresponding change in calcium (5 ppm or 1.1% of the calcium) is not easily detected.

Maybe a little over 1dhK per day. I've been dosing around 1tbsp of Arm&Hammer baking soda mixed into one quart of ro/di every day into 250ish gallons of tank water.

I plan on switching to soda ash on a dosing pump once my bucket of soda ash arrives from BRS. Then eventually something like All for Reef or Balling once I have actual calcification happening. Right now the goal was just to maintain alk since calcium and mag seem stable.

 

[Randy Holmes-Farley]

Maybe a little over 1dhK per day. I've been dosing around 1tbsp of Arm&Hammer baking soda mixed into one quart of ro/di every day into 250ish gallons of tank water.

I plan on switching to soda ash on a dosing pump once my bucket of soda ash arrives from BRS. Then eventually something like All for Reef or Balling once I have actual calcification happening. Right now the goal was just to maintain alk since calcium and mag seem stable.

I'd personally maintain the alk as needed. The baking soda is a fine way to go. I cannot see it hurting anything.

 

[ScottF]

I'd personally maintain the alk as needed. The baking soda is a fine way to go. I cannot see it hurting anything.

Will do. Thanks so much!

 

[ScottF]

Interestingly, I started having an algae outbreak and I scrubbed most of my rock with a toothbrush. After brushing the rock, my alk consumption dropped off.

I was dosing 200ml of soda ash solution per day to keep my dKH at 9 (even before I added any coral) and suddenly my alk jumps up to 9.7 dKH. Luckily I had my Apex set to turn off the dos and send me an alert if the Trident read higher than 9.5 dKH.

I've slowly dropped to 9.5 dKH with the dos off for about 24 hours. Prior to yesterday I would have been at like 8.5 dKH by now.