Difficulty maintaining ALK

My tank been running pretty good for last 2 month. My params were stable.

I test every 3..4 days for pretty much everything. My mag and cal been stable for 6 weeks and still are. CAL is between 400 and 450 and mag around 1300. ALK used to dip down, so I dose carbonate when it gets below 6.5 and usually keep it right around 9. I used to have to do add carbonate maybe every 7..8 days.

Last week tings changed without me changing anything. My calcium and mag are still table, but my ALK is dropping very quick. I dose, get it back up to 9, then 2 days later it's back at 6.5. PH is stable at 8.3. CAL still between 400 and 450. Mag at 1350. All other water params perfect. Sal stable at 1.026.

What would cause ALK to start dropping so quick even tho everything else is perfectly in check?

Thanks.

 

I am guessing you have a reef tank?

Growth in your corals have a lot to do with alk usage along with pH maintenance also. I suggest not letting your alk drop below 7 before you dose alk. You should try to avoid dosing more than 2.8 dKH of alk a day unless your system uses more. The steadier you keep the level the happier the system and corals. I suggest getting a doser to maintain you alk level.

 

Can you recommend a doser model?

What exact brand/model chemicals do you dose? At what schedules?

I realize shcedule gonna be specific ot my tank, but would like to get an idea of what a tank may run like.

Thanks.

 

There are a variety out there. I would suggest going to Bulk Reef Supply and getting all you need from them.

I am using Rio lift pumps on a 12x per day schedule using a controller.

You will want to look at dosing 1.3 dKH per day. BRS has a calculator to help you figure it out.

 

Awesome. Thank you!

 

From your discription, I am thinking it is the test kit. If everything else is stable, check the experation date on the kit.

 

I will. Tho i doubt it would read 9 after dosing if it was bad and then drop so quickly back down.

 

Kit has exp date of 09/2013, but, maybe you're on to something. Today when I got back I noticed a lot of white dust over rocks. Maybe due to kit being bad, I actually been adding way to much carbonate and now am experiencing the dreaded calc snow?

Noticed a lot of white dust all over power heads and heater too.

 

That is why I was questioning the kit. Also, if I get different readings from any kit, I will sample from a couple different places such as, in strong flow, less flow and even in the sump.