raising KH

My KH has been around 7, corals are not happy. I've been adding buffer everyday to get it up since Saturday morn. It's Wednesday morning and it's only just 8. Cal levels are 500+. I use RO water as top off, but with that, am I just making the KH go lowe by putting the RO water with 0 KH in the tank? I want to start lime water, but I've been told to get the KH up to around 10. But my lime water has a KH of 12+. Won't wouldn't that help the tank now?

 

You must test Mag. levels.Without knowing its value you will be chasing numbers like a ping pong ball.
My reef tank generally runs between 7-9 DKH.

 

+1.....Need mag values to address alkalinity.

 

Okay thanks. I was wondering if it took really long to get KH up.

 

It does if your Mag. is low.

 

When calcium is very high (like your 500) and KH is low, correcting cal/alk ionic balance becomes more and more difficult. You should get your calcium down to 400-440 level, that will make it easier to get KH up. Once they are balanced, you can raise both together.

Here's cal/alk balance chart:

 

Those tables are meaningless without the proper Mag, level.Achieving ionic balance is fairly simple.Keeping it there is not.

Step one test Mag. Step 2 Test calcium and step 3 Alk.
If step 1 is low correct it until you reach your desired number.
Test all 3 and see if any adjustment is necessary.
Test at the same time every day; it matters.You will then be able to see what your system uses.Your Alk. will rise and fall every day and swings are natural.Your Calcium value and your Mag. level should be more stable.
DON'T chase numbers!!!!!!!

 

I think my advice still applies, if his mag is on target

 

Absolutely I was just going to edit cause I came off like a jerk when I read it.lol Sorry.
Lots of people neglecting mag. lately and I seem to have developed a chip.

 

I never knew alkalinity fluctuated through out the day, I know PH does. Always learning.