Help with Ca & KH levels

[JMW]

ok so guys, I have about some SPS frags(BN & digi, etc) in my 10G nano.

I have been monitoring my Ca(Salifert) & KH(Nyos) over the last week to understand the utilization rate:

21st Oct   -  370 Ca  -  6 KH

22nd Oct  -  390 Ca  -  6 KH

23rd Oct   -  395 Ca  -  7 KH

24th Oct   -  390 Ca  - 7 KH

Have two questions:

1) Any idea why My Ca & KH didn't drop as the week went past? Expected them to drop cos of the hard corals...

2) What would be a good choice for balanced additive to bump up both my Ca & KH? Am targetting for 420 Ca & 10 KH.. Would Salifert all-in-one work? Don't have reactor or dosing pump so planning to add via ATO or direct pour into tank. For that reason, am not so keen on kalk, afraid of the possible PH swing if OD.

Please share your opinions & experience! Thanks in advance

[xiggie]

In order for kh and cal to drop , something needs to consume them. 

Even when you have Sps in your tank it doesn't mean that they are consuming them. 

The Sps needs to be stable and growing before u see a significant drop in kh and cal .

There are lots of factors that can effect the stability and growth of Sps or infact all corals.(no3,po4 especially )

i would pay more attention on the no3 and po4 and get them in check before looking at kh cal and mg or other trace elements. 

For a 10g nano , I think those off the shelve product would be good enuff. Should not effect ph or other stuff that much.

Edited October 26, 2015 by xiggie

[JMW]

Hi bro, thanks for your advice.. I noticed growth on the SPS as I stare at them everyday

but ok on a more serious note, I do compare the SPS skeleton shape as the days pass by & notice that there's elongation & also start of branching, that's why I thought there is growth which consumes Ca & KH...

my nitrates are steady at 5, phosphates are ard 0.1, I know not ideal so I'm trying to bring it down with GBPO4.

[ShadowHunter]

I used to have a 30G SPS dominated reef (decommed). Weekly WC of 10-15% with a good salt should replenish and maintain the parameters. When your SPS are growing well, you will notice that WC can't catch up with the consumed carbonate and calcium. Then it's time to consider dosing with stuff like C-balance etc with a dosing pump. Do not do manual dosing since ur water volume is small and any slight overdosage can be disastrous. Do take note of ur SG swing due to evaporation and how u do topping up.

Xiggie is right, sort out the Nitrate and Phosphate issues first. WC is key!