Kalk And Ro

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OK i was reading a thread now now about topping up with RO water and i think it was jacquesb that said one must add kalk to the RO?

firstly what is kalk?
secondly ive topped up with about 75 litres of R.O already and P.H is still 8.4
lastly is kalk expensive? cause this hobby is too much$$$ already
 
Hello Geoffrey -

Here goes:
Kalkwasser =
Calcium hydroxide mixed with white spirit vinegar mixed with RO water....

Calcium Hydroxide = "Slaked Lime" or "Gebluste Kalk" - and this you can get from ANY decent chemist. It should be on the rack with chemicals in powder format.
You should not pay more than +-R5 to R6 per 50 grams box of Slaked Lime....

The ratio that the mixture is mixed to, that I use, is:
+-15 grams of Calcium hydroxide, mixed to +-200-250ml of white spirits vinegar, mixed to +-2 litres of water.

I then dose +-50ml of this mixture at least 3 to 4 times per week to the return section of my sump....

You can add this directly to your RO container as well, if you have an auto-topup....

Hope you understand.
 
After about 15-20mi a white layer forms at the bottom of the container... Do i mix it when i want to add to my tank or pour only the clear in?
 
OK i was reading a thread now now about topping up with RO water and i think it was jacquesb that said one must add kalk to the RO?

firstly what is kalk?
secondly ive topped up with about 75 litres of R.O already and P.H is still 8.4
lastly is kalk expensive? cause this hobby is too much$$$ already

buy it from your chemist ,very cheap, kalk, calcium supplement, ph is fine
 
After about 15-20mi a white layer forms at the bottom of the container... Do i mix it when i want to add to my tank or pour only the clear in?

this means that your solution is saturated, pour only the clear liquid otherwise you will cause a calcium storm in your water , this is where the calcium is pulled from your water resulting in a ph drop (ps kalkwasser ph approx 12)
 
Don't buy kalkwasser from a LFS, go to a chemist and buy Slaked Lime. It's dirt cheap.
 
OK i was reading a thread now now about topping up with RO water and one must add kalk to the RO?
The easiest way. You must automate

firstly what is kalk?
CaOH Calcium Hydroxide
secondly ive topped up with about 75 litres of R.O already and P.H is still 8.4
Thats a lot of RO. Are you dosing with buffer
lastly is kalk expensive? cause this hobby is too much$$$ already
No.......Copy Jac.
 
i used ph propper 8.2 a little while back and that seems to have helped. but its expensive and i dont know how long it will last. my Kh is 12 which is also good right?

do i only need to add kalkwasser once my tank has corals in it? cause i have a very low bio load at the moment and no corals so i doubt i'll need hey?

just worried about my P.h fluctuating too much by topping up with R.O water
 
IMO With your KH @ 12 I suggest you check your Ca and Mg because I bet they will be out of sinc.
Better would be
KH8-9
Ca 380-430
MG 1150-1400
 
OK i was reading a thread now now about topping up with RO water and i think it was jacquesb that said one must add kalk to the RO?

firstly what is kalk?
secondly ive topped up with about 75 litres of R.O already and P.H is still 8.4
lastly is kalk expensive? cause this hobby is too much$$$ already

Good info so far... but just to add:

  • You don't NEED to use kalk with the RO, especially if the tank is still young, and you don't have many corals.
  • Your pH of 8.4 is perfect - why do you want to change it? Keep in mind that adding kalk will INCREASE the pH, and you don't want it to increase above 8.5 without good reason.
  • I would suggest that you check your alkalinity and calcium level before making the decision to add kalk.
Adding kalk is a very good thing for the long-term stability of your tank, BUT it does contain some element of risk (can kill everything in your tank!) if you're not careful and knowledgeable - so first determine if you need to add it at this point in time.

Hennie
 
ro water won't bring ph up or down

Will bring it down as ph of RO (or at least mine is 7), so it would decrease your 8.4 if you did huge water changes with RO only.

But as top up doesn't effect to too much
 
yip, i ment with top up.
and with wc it won't do anything if you use the right salt.
Am i right war?
 
ok just an update on this thread. i have now got 2 little monty frags and a ricordea. i want to bring my calcium levels up a bit as i've noticed a slowing in my coraline algae growth.

my Alk is at 9
P.H 8.5

Gonna go to the chemist and buy some slaked lime (calcium hydroxide) gonna add 3 tsp of this to my R.O top up and see if it makes a difference.

350l 4ft tank...
 
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