alk to high how to lower?

[frags75]

I just did a alk test and it is very high reading 6.5 meq/l and on another test kit it was 18dkh. This tank has been running for 5 months and this is the first problem I have encounterd.
salinity 1.025
ph 8.1
cal 380
nitrate 0
nitrite 0
ammonia 0
I just set up my reactor last week and it seems to be dialed in right. The effluent ph fluctuates between 6.6 and 7.0 the controller is set at 6.5, my drip rates are 60ml or 1/4cup per minute for effluent and 30 bubbles per minute co2. What could have happened? How can I correct this? This is the first time I ever noticed any drastic change like this. LFS said maybe a bad batch of salt. Any ideas or help please. Thanks in advance.

[bertoni]

Once common cause of high alkalinity is the use of pH buffers, which are just high-pH alkalinity supplements. You could try mixing some fresh saltwater and see how it measures up.

I would disconnect the calcium reactor, and let alkalinity drop on its own. A calcium chloride product, like Kent Turbo Calcium, can be used to keep the calcium in line.

If any animals are having trouble, then some water changes should help.

[The Shan Man]

Another option would be to disconnect the reactor and then do a water change to help bring it down. If it doesn't come down on it's own fast enough for you.