Very low ALk.

[jjmcat]

Heres my problem.My calc is 430 and my alk is 6.1.I evaporate around 2.5 gallons a day.I have a dosing pump for my top off that feeds the water into my sump out of a 5 gallon container.My total water volume is 150 gallons.I did just treated for reb bugs and have changed over 90 gallons of water in the past week.Shouldnt this have raised my alk?I am currently adding reef builder to my top off water that contains the pickling lime.

[MarineFlake]

Heres a suggestions...Check your mg levels, should be ~3 times your ca. (IE 450 x 3 = 1350PPM)

[bertoni]

Adding Reef Builder to limewater is a bad idea, as that can cause precipitation. I'd ditch that limewater, and mix up a new batch. The alkalinity in the tank can be corrected with baking soda dissolved in RO-DI water. This caculator will help with a dose:

http://home.comcast.net/~jdieck1/chem_calc3.html

There's no reason to dose magnesium to 3x the calcium level. Magnesium should be fine at around 1275 ppm. I am not sure where the 3x idea originated, but I don't know of any chemistry behind it. NSW doesn't match that formula, on average, as I recall.

[jjmcat]

What could have caused this huge drop in my ALK?

[jjmcat]

One more thing.Am i adding to much limewater to my system and if so should I lower the amount of lime to my top off?I add 5tps per 5 gallons.

[bertoni]

5 tsp per 5 gallons is fine. Alkalinity could be dropping for any number of reasons. Calcification drops alkalinity more rapidly than calcium, percentage-wise, so that's the most likely issue.

[jjmcat]

Thanks for the help.Ill keep you updated on this.

[jjmcat]

[QUOTE]Originally posted by bertoni
[B]Adding Reef Builder to limewater is a bad idea, as that can cause precipitation. I'd ditch that limewater, and mix up a new batch. The alkalinity in the tank can be corrected with baking soda dissolved in RO-DI water. This caculator will help with a dose:

Do I bake the baking soda first?

[bertoni]

I wouldn't, in this case. Baking the bakig soda will cause it to raise pH when dosed, which isn't a good idea for large doses, in most cases.

[MCsaxmaster]

Agreed, using just straight baking soda will elliminate the chances of rapidly raising pH (it will lower pH a bit, actually) and alkalinity can be raised faster this way (probably in a single shot w/o problems). Once calcium and alkalinity are at acceptable levels you can maintain the balance with kalk (which is a balanced supplement).

cj

[jjmcat]

The ALK level is up now so I thank you all for your help.I may have overdone it a bit.Its now at 12 and my calc is at 350.Im hopeing it will level out a bit with my normal 21 gallon water changes.