Alk won't rise.

[rvlcf]

I have a medium to low stocked Reefer 450 about 4 months old. I am dosing Kalk in the top off at max strength of 2 teaspoons per gallon. Also dosing BRS soda ash solution every other hour through dosing pump, with BRS calcium dosing on the opposite hour. Don't know the exact amount of alk per day, but its at least 50ml. Alk reading is between 6 and 6.5 depending on the test. I have been manually adding 80 ml alk the last two days, on top of the normal dosing trying to get the alk up. I'm still getting the same readings even after dosing at least 150 ml of alk the last few days. What gives?
Params are:
Cal 420
Mg 1400
ph 8.2
sg 1.026

I'm using a Hanna alk checker. Tried two different reagents, with roughly the same results, and ran a salifert also which gives me the same readings. It's not the test kits.

Thanks in advance for the help.

 

[hann1bal]

I would double check my calcium and magnesium - make sure they are right. But otherwise im just a spectator as i havn't started kalk or 2part yet.

I'll be interested to see what people say.

 

[steallife904]

maybe your soda ash solution is to watered down???? either that or your just not dosing enough and need to increase. I dose the BRS soda ash as well, about 45ml a day and it keeps my 150gal at 7.7dkh. Everytime I have to mix a new jug of the alk I watch the brs video (as a reminder) to make sure I mix as they instruct.

 

[oseymour]

I have a medium to low stocked Reefer 450 about 4 months old. I am dosing Kalk in the top off at max strength of 2 teaspoons per gallon. Also dosing BRS soda ash solution every other hour through dosing pump, with BRS calcium dosing on the opposite hour. Don't know the exact amount of alk per day, but its at least 50ml. Alk reading is between 6 and 6.5 depending on the test. I have been manually adding 80 ml alk the last two days, on top of the normal dosing trying to get the alk up. I'm still getting the same readings even after dosing at least 150 ml of alk the last few days. What gives?
Params are:
Cal 420
Mg 1400
ph 8.2
sg 1.026

I'm using a Hanna alk checker. Tried two different reagents, with roughly the same results, and ran a salifert also which gives me the same readings. It's not the test kits.

Thanks in advance for the help.

According to BRS Calculator you would need about 85ml of alk to get from 6.5dkh to 8dk - That's assuming you have 80 gallons of water. (I have about 55 gallons of water after displacement in my Reefer 350)

Assuming you mixed the solutions properly - you are dosing too much - most of it is probably precipitating out into the sand.

I have a medium stocked reefer 350 with LPS, softies and some SPS frags growing, I'm dosing 16ml of calcium and alkalinity per day to keep my levels steady at 8.5. If my levels start to drop, I notice my PH is on the low side.

You should also check your magnesium, you cannot get alk or calcium to rise if magnesium is low. I do water changes once a month and that's not enough to keep up with magnesium demand - I have to dose.

 

[Sk8r]

if your magnesium is below 1200, it could be your problem. Bring mg to 1350. IF that's not it, suspect your test and stop adding buffer until you've confirmed the result with your lfs.

 

[bertoni]

I get about 150 ml to raise the alkalinity by 3 dKH. Personally, I'd shut off the doser pump for a bit and dose twice a day by hand. You could measure the alkalinity 10 minutes or so after dosing, to see what happens. If you're worried about precipitation, you could switch to baking soda for a few days. It's less likely to precipitate. Getting a second opinion on the alkalinity test kit might be useful, too. We see a lot of problems with test kits.