Strange alk demand on new tank

[reefkeeper2]

I've just finished a new build on a 400 gal tank. Total water volume is around 500gal. For the past year and a half I've had some fish and corals in holding tanks in my basement waiting for their new home. They moved in to their new digs last week. I can't understand why there would be such an increase in alk demand for the new tank when I have the same number of animals as I had before. Kalkwasser additions by itself was sufficient to maintain my alk and calcium levels. Now I'm trying to tune in my calcium reactor plus I'm dosing Alk to keep up. Any explanation? Could it be precipitating on the new sand and rock?

 

[arking_mark]

I've just finished a new build on a 400 gal tank. Total water volume is around 500gal. For the past year and a half I've had some fish and corals in holding tanks in my basement waiting for their new home. They moved in to their new digs last week. I can't understand why there would be such an increase in alk demand for the new tank when I have the same number of animals as I had before. Kalkwasser additions by itself was sufficient to maintain my alk and calcium levels. Now I'm trying to tune in my calcium reactor plus I'm dosing Alk to keep up. Any explanation? Could it be precipitating on the new sand and rock?

New tanks will usually have increased abiotic precipitation until surfaces become poisoned with phosphate and such...

 

[Randy Holmes-Farley Verified Community Expert]

How much daily alk consumption are we talking about?

How long has it been going on?

is nitrate accumulating?

 

[Ultra Aquatics]

With these larger systems even small changes require much more dosing. On my 400g Sps tank I have my calcium reactor maxed out plus using 3000ml of kalk slurry and still need 2 part to supplement. I just ordered a much larger Cal reactor from Geo to compensate.

 

[reefkeeper2]

How much daily alk consumption are we talking about?

How long has it been going on?

is nitrate accumulating?

Only one week. Nitrates and phosphates are undetectable, so I've been dosing nitrate up to get a reading of 2.5. I don't know the consumption yet because I'm still making adjustments to compensate. I have a kalk stirrer that all top off goes thru. I'm using your formula for the Alk dosing but I just started doing that yesterday. I started at 350ml a day but just upped it to 500.

 

[reefkeeper2]

With these larger systems even small changes require much more dosing. On my 400g Sps tank I have my calcium reactor maxed out plus using 3000ml of kalk slurry and still need 2 part to supplement. I just ordered a much larger Cal reactor from Geo to compensate.

That's what my last system was like. I only have a few sps at present.