is it normal ?

[angelfish]

my 100 g (includes 25g refugium) tank has been running for about 4 years with mixed of soft & hard corals. i have a CaCO3 reactor installed about a year ago when i started to keep sps.

just recently my CO2 ran out and when i got a new refilled cylinder home, found that there's a leak at the cylinder head. i sent it back to the shop and get it fix. but the shopkeeper said he has to send the cylinder back to factory for repair, and unfortunately there's no refilled cylinder left to exchange. it'll take few days to get back to me.

i'm a bit worry that the alkalinity will fall because there's no reactor running. i test the alkalinity after i've made water change and the alkalinity is at 9 dKH. i test it again after 24 hours and it drop to 7 dKH.

the question is, is it normal to have a two degrees drop of alkalinity in one day?

 

[chris&barb]

it can be if you have a lot of calcifying organisms in your tank. in the mean time you can easily and cheaply maintain your Alk with baking soda. if you go here http://reef.diesyst.com/ it will tell you how much you need to add to keep the levels you want

 

[LakeEd]

Your Calcium Reactor is not only supplying your system with Alk, but a matched amount of Calcium as well. While you are without your Reactor, you might conceder dosing Kalk... since it will also give you balanced addition of Alk & Calcium. From your usage, you may need to setup a slow continous drip to keep up with your tank's demand, but at least it would be a balanced help with your situation.

 

[Boomer]

I agree with Ed but you will still have to monitor both as we do not know what the Ca++ and Alk demands are / say. You may or not need to boost one, as the the kalk drip may not be enough .

 

[angelfish]

thanks guys,

i've learned something that i should have ask long time ago

just a thought that can i just slow down the carbonate hardness demand if i reduce the light hours or intensity ?
(i guess the coral grow rate will be affected, but i felt that they are a bit out of control in my tank)