Kh/ALK Dropping Kalkwasser Top Off Advice

[jmc1024]

Hello all,
I a 65 gallon mixed reef tank. I have about 25 corals all bought as frags. I only have 1 SPS coral in the tank it's a small Montipora (but growing nicely). The rest are all softies mostly zoos and lps. My chemistry is mostly good as of 9/24: PH 8.2, ammonia 0, nitrite 0, Nitrate 0 (or close too), KH/Alk 10.0, Calcium 480, phosphate .03 (I"m working of getting this down). I have been dosing 1 tsp of Kalk water to 1 gallon of top off. However it doesn't seem to be enough to keep my Kh/Alk in place. 9/24 it was 10.0, 9/25 it went to 8.0 and by 9/29 its at 7.3. My calcium has been stayed pretty steady. According to bulk reef supply you can dose up to 2 tsp of Kalk to a gallon so I should be able to add more. However I was hoping to get some opinions. Is this normal? I've only been keeping coral for about 8 months so I'm pretty new to the hobby. However it was my understanding that softies don't really require much dosing. Was hoping to get some thoughts. Lastly I should mention that almost all of my corals are doing well and growing nicely and I am getting some nice coralline algae. Which I assume would lead to more consumption. Thanks for reading and your advice.

 

[Adamc1303]

You can try adding more Kalk to the top off water to get it a little more concentrated. However since you're adding the Kalk via top-off you have no way of regulating how much is added to the tank. My guess is that since the weather has been cooling off, your tank has less evaporation which means that less Kalk rich top-off water is being added. Can you add a doser for the kalk? Bare in mine you will need to find a medium with a doser as well because the Kalk dissolves in freshwater and you're limited with how much fresh water you can add before lowering your salinity level.

 

[theMeat]

Dose a lil more kalk until you find a balance. When you dose kalk in ato you have to consider sometimes of year your tank losses more water through evaporation so you must adjust your amount of kalk per gallon so it's the same amount of kalk over a given time.
Also wouldn't sweat phosphate at .03

 

[jmc1024]

Thanks for the advice, do you guys think that it's normal that my corals are using this much Alk? FYI I seem to go through about 2 gallons of top off every week.

 

[theMeat]

Hard to say if that's normal from where i'm sitting. Can tell you that when alk goes down cal goes up and vice verse. And when ph goes up or down, alk usually follows somewhat. Also, when magnesium isn't within a good range, alk and cal can swing around alot making it hard to figure out and nail down