keepin' my alk up

[CoryDude]

Besides viagra, what's the best way to increase my tank's hardness?

For as long as I can remember, my tank has always had a problem keeping the dkh above 7. I use a knop reactor (effluent tests at 18-20dkh) and add seachem reef builder to my top off water.

The main reason I'm asking is that I'm seeing a little STN on the base of some of my sps.

PH: 8.3 (day) 8.2(night)
NO3: around 5 mg/L
PO4: undetectable
Ca: 400-425 mg/L

[ErikH]

Kalk homeboy, kalk.


Stuff works wonders. You could use the slurry method to bring it up quickly, then just maintain it through your ATO. Kalk fully saturates the water, and increases it's PH to 12. As long as you make sure your PH in your ato is 12.0, you should be great. If you want to talk about it you can call me or come by and I can try to help you out as best I can.

Just remember, your ph in your ATO will never go above 12, because the water is completely saturated at that point. No more calcium hydroxide can be forced into the water, basically. In a reactor, you can add a bunch of kalk. Each day it gets stirred, which helps to resaturate the water, and use all of the available kalk to do so, which allows you to go for longer. In an ATO though, you have air exposure, which I believe is why they tell you to check it a little more often to make sure it does not go bad and your ph stays high.

That is why you dose it at night through your ATO, to combat the low swing at night, after the lights go off.

[ErikH]

ok, just so you know, it's late, so hopefully someone else can fact check my statements!

[acropoorer]

Try getting your effluent up to 30-35 range. Don't know your reactor, but increase effluent kh and drip until you get your tank in the 11 -12 range. this may lower your ph but that is less critical than keeping kh above 8 always. All reactors are flakey, but you will have fewer issues with high kh than with low. I have run for several days at 16 and not had a problem with my corals. Also, once you get to the 12 range if your ph is low you can improve it by running your effluent into another container with an air stone to drive off CO2, then drip it into your tank.

If you have a lot of sps running your reactor hard will likely lower ph but I ran for a year in the 7.6 to 7.9 range before adding an air stone, now I run in 7.9 to 8.1 range, but have to run my reactor hard as I have a lot of large sps. When I had fewer corals my ph ran higher, but I never had an issue the the lower ph, just feel better having it higher with the air stone.

Hope this is helpful.

[CoryDude]

Erik,
I forgot to mention that I just started dripping kalk at night to supplement my ca. My reactor couldn't keep up with the demand and ca fell to 350. I've used kalk since I started in '95 and never understood why you had to follow the steps you did in using it. Thanks for explaining the science behind it, though. I may just keep doing that and see what happens.

Erik, off subject, but did you use a studio kit or code from scratch on your websites? If so, what language did you use (java, python, etc). I'm trying to learn python, but the delimiters throw me off evertime. I'm too used to java's and c+'s standard delimiters.

Acropoorer,
how did you adjust your effluent's settings (drips per second/bubbles per second) to get a dkh that high? Since I switched over to a sps dominant tank, I never adjusted my reactor's settings to keep up the higher ca demand. If I have trouble keeping my levels balanced using the reactor and kalk as Erik mentioned, I may just dump the kalk and go with your recommendations.

The only problem I see is the low ph. My experience has shown my tank has problems with a ph below 8.0. My coral growth came to a stand still even with a dkh of 8-9 and ca of 450 when this happened. But this was when my tank was lps.

I did reroute my reactor's output line nearer to the overflow pipes in the sump when I installed the hiatt filter. I also installed some pool type strainers to shred the water and help drive off co2 from the reactor and the hiatt. Maybe this could help limit any ph lowering if I adjust my effluent to achieve your recommendations.

[CoryDude]

Forgot to mention, that I my reactor may not even be able to reach those levels. It's the smaller size knop reactor. I got it when I still had lps so I didn't need much at the time. I may switch over my korallin denitrator to a ca reactor since it can hold more media.

[swjim]

If I read your original post correctly you want to boost your alkalinitity but are ok with the calcium level, right?

If so, both your calcium reactor and kalk will add calcium and alkalinity in a fairly balanced ratio. If you want to perform an adjustment of the alkalinity without changing the calcium level you can do so by using sodium bicarbonate (baking soda). You can find some great info here: http://www.advancedaquarist.com/issues/nov2002/chem.htm

[CoryDude]

If I read your original post correctly you want to boost your alkalinitity but are ok with the calcium level, right?

If so, both your calcium reactor and kalk will add calcium and alkalinity in a fairly balanced ratio. If you want to perform an adjustment of the alkalinity without changing the calcium level you can do so by using sodium bicarbonate (baking soda). You can find some great info here: http://www.advancedaquarist.com/issues/nov2002/chem.htm


Correct. Saw some people on RC recommended baking soda, but didn't have too much info on it. Thanks for the link!

[Muddybluewater]

I would suggest checking your Magnesium also. If it is low it is hard to raise your Kh

[CoryDude]

Zone 4 is where I'm at. Since my ph is good, I think I might just try using baking sode to bring up my total hardness. It usually around 3.1-3.2 meq/L. Then'll I'll keep dosing kalk and use the reactor to keep up with it from there.

I've got a bottle of Arm and Hammer Pure Baking Sode. The ingredients list only sodium bicarbonate. So I guess I'll be ok if I use this, or is there a better type/brand to use?

[swjim]

Arm and Hammer should be fine. I would just be careful to make the adjustments slowly.

[swjim]

And I agree with Muddybluewater, you should check your Mag levels too if you haven't already.

[txav8r]

Ask Bstreep about this. I think you need to bake it in the oven first to drive off some ingredient.

[swjim]

Ask Bstreep about this. I think you need to bake it in the oven first to drive off some ingredient.

IIRC, baking the baking soda (say that ten times fast) changes it to soda ash, he would want to do this only if his PH was lower than 8.2.

[CoryDude]

Mag was the original direction I tried a while back. I keep it around 1300meq/L.

I think part of my problem was constantly high nitrate levels. I read an article (I think it was from advancedaquarist) where someone postulated that high nutrient levels could cause low alk. Something about causing bicarbonates to precipitate out of the water faster. I need to find that link.

[txav8r]

Found this:


Actually, you do NOT want baking soda. Baking soda will LOWER your pH, in many instances. It's pH is around 7.8-8.0.

And, it will raise your alkalinity.

What WILL raise your pH and your alkalinity is anhydrous baking soda: Put box of baking soda into a baking dish (very clean), and put it in the oven for an hour at 350 degrees. This drives off the CO2 - which ist what lowers your pH - and make sodium bicarbonate into sodium carbonate. I take a box of this and put it in a 3 liter bottle of RO/DI water, and dose with it. The pH of sodium carbonate (anhydrous sodium bicarbonate) is 11.6 - and pH is a logorithmic scale (10 is 10x what 9 is).

This is a great link: http://jdieck1.home.comcast.net/~jdieck1/chemcalc.html

I'd guess your biggest problem is too much CO2 OR a bad test kit - either pH or Alkalinity. As one who chased an Alk problem a few years ago because of a bad kit, HAVE SOMEONE ELSE TEST YOUR WATER! For pH, your water sample needs to be just water, in a sealed bag (no air).

Oh, yeah: If you dosed Mg, did you test for it? The cardinal rule in Reef Chemistry: "Don't dose anything you don't test for".

[CoryDude]

Jack, do you have the link for that discussion? I'd like the see the op.

[txav8r]

Ask and ye shall receive!

http://www.maast.org/forums/showthread.php?t=52826&highlight=baking+soda

[CoryDude]

:applause: Thanks Jack!

[Bill S]

Cory,

Because pH is tough to maintain high, I'd probably use the anhydrous version of sodium bicarbonate (sodium carbonate). Just be careful, and monitor your pH. After dosing, it will take a few hours for the tank water to be stabilized.