I seem to continually be using ALK faster than CAl

[110galreef]

Is this ok, or does it have to be the same??.....

I have been dosing 80ml of each for last few mos. AlK would seem to always fall from ~ 9 to about 8.0 over 7-10days. I would then bring it back to about 9.0 over a day or so. Then again 7-10 days later with same dosing it would drop to 8.0ish.

All the while CAL seems to hold pretty steady at ~ 420

I have been at 90ml ALK & 80 ML CAl and still about the same. So I went to 100ml ALK & 80ml CAL.

Is this OK? or something else going on??

I have been doind 15% WC every 4 weeks of late.

Also I dose these amounts broken out 6 times a day and the ALK is first and then CAL 5 mins later if it matters?

 

[disc1]

Because there is so much more calcium in the water than alkalinity, it sometimes looks like alk is moving but calcium isn't. For every 1dkH of alk you use, you only use up about 2ppm of calcium. So you might have to use up 10dkH of alk before your test kit is going to be able to see any difference in calcium.

 

[110galreef]

ok, confused here sorry. So is it ok to dose different amounts? Or are you saying ignore my ALK readings and dose based on the CAL reading and keep them the same dose?

Also I have checked my ALK reading with both salifert and hanna and both seems to be about the same.

 

[Randy Holmes-Farley]

Unless calcium is already higher than you want, stick to equal parts dosing. It won't rise much.

 

[disc1]

Dose your two part based on your alkalinity numbers and the calcium will sort of fall into line. That same ratio exists in the concentrations of the two parts. So when you dose them at equal concentrations, then they should each keep up with consumption.

 

[110galreef]

Ok, so bump up my ALK to 100 as well as my CAL to 100ml even tho CAL appears to be staying consistent?

I will first do a small WC, check everything, get CAl & ALK at the numbers I want then dose at 100ml/day and see how it goes.

 

[Randy Holmes-Farley]

If you use both parts equally to bump the tank starting at 8 dKH to 10 dKH, the calcium would only jump from 420 ppm to 434 ppm, so you'll hardly notice that, and in fact, calcium may have been dropping and you just didn't notice it over the noise of the calcium testing.

 

[110galreef]

can calcium be too high to an extent. Meaning if it gets to say 460 should I worry or just let it goes based onmy ALK?

 

[mos90]

im pretty sure as long as u are under 500 u are ok. ill let the experts comment. but you still want to try to keep it balanced as much as possible.

 

[110galreef]

So what is balanced.....are you saying there is an equilibrium that my tank will adhere to?

my ~ 8.0 ALK & 420 CAL
so if I bump my ALK to 9.0 thern CAL will be like 430's to be in equillibrium/balanced?

And my tank won't really hold say a 10.0 ALK & 420 CAL...rather just keep precipitating back to the
~8.0 & 420 i keep netting?

Should I just stick with the 8.0 & 420 it keeps wandering to as long as it is consistent as within ideal specs.

 

[Randy Holmes-Farley]

Calcium should not rise noticeably if you dose the two part to maintain alkalinity, but if it gets much over 500 ppm, I'd stop dosing that part for a while.

 

[mos90]

8/420 , 10/420, 9/430 all fine. 7/500 13/380 not balanced.

stop dosing for a bit like randy said and let calcium fall to 430ish. then resume equal 2 part dosing , after that and keep an eye on it.

my tank is 9/440 fyi.

 

[110galreef]

Calcium already is 420. It's my Alk that seems to keep falling from 9.0 to 8.0 every 7-10 days after I bring it back up to 9.0 from the 8.0 it falls to. All the while calcium stays happy at 420ish.

 

[mos90]

i wouldnt fight it. stick with 8/420. if it alk keeps falling below 8 then adjust 2 part. its not good to keep bouncing from 8-9 every week. what results did u have when u bumped up 2 part to 100/100?

 

[Randy Holmes-Farley]

Calcium already is 420. It's my Alk that seems to keep falling from 9.0 to 8.0 every 7-10 days after I bring it back up to 9.0 from the 8.0 it falls to. All the while calcium stays happy at 420ish.

As mentioned above. Calcium is far, far slower to change based on under or over dosing of both parts (that is, really underdosing both calcium and alkalinity) than is alkalinity. This is easily shown mathematically, and is experimentally observed in nearly every tank with is dosing a two part, but not quite enough to maintain alkalinity.

So just focus on alkalinity in determining the dose and calcium will follow along.

If you really want to get into the details, this has them all:

When Do Calcium and Alkalinity Demand Not Exactly Balance?
http://reefkeeping.com/issues/2004-12/rhf/index.htm

 

[disc1]

Calcium already is 420. It's my Alk that seems to keep falling from 9.0 to 8.0 every 7-10 days after I bring it back up to 9.0 from the 8.0 it falls to. All the while calcium stays happy at 420ish.

So that's telling you what the two part dose should be. I don't have the calculator pulled up, so I can't say in mL, but it's going to be about 1dkH worth spread out over 7-10 days.

You will find that your calcium has actually been dropping by a proportionate amount. You just can't see it with a test kit. If you suddenly find that calcium goes up over 500, then stop the calcium part until it falls back down.

You should end up dosing equal amounts, but if you do regular water changes and your salt mix isn't exactly where you keep the tank then you might end up doing a little more of one or the other. But even in that case, calcium levels are going to move slowly and you have plenty of time to catch the effect.

 

[110galreef]

Ok. Just tested. CAL 420 and ALK 9.0 (salifert). I will set both to dose at 95 ml/day and see how it goes. I will report back with tests in 4 days and a week and 10 days.
Thanks

 

[mos90]

Sounds good. Keep us updated.

 

[110galreef]

As mentioned above. Calcium is far, far slower to change based on under or over dosing of both parts (that is, really underdosing both calcium and alkalinity) than is alkalinity. This is easily shown mathematically, and is experimentally observed in nearly every tank with is dosing a two part, but not quite enough to maintain alkalinity.

So just focus on alkalinity in determining the dose and calcium will follow along.

If you really want to get into the details, this has them all:

When Do Calcium and Alkalinity Demand Not Exactly Balance?
http://reefkeeping.com/issues/2004-12/rhf/index.htm

Thanks for the article. That helps alot.
I will keep you all informed and hopefully all is works out at the same dosing levels!

 

[Lynnmw1208]

I have this same problem in my tank! I really think it's the reef crystals I switched to from red sea coral pro....

I have just been dosing alk and not calcium at all. My calcium is rather higher than yours though at 470-480 at times. My alk drops from 8.5 or so after a water change to 7.3 which is a rather large drop within a week. I feel like I always struggle to keep that number above 8dkh. I'd be happy with an 8 lol.

What 2-part are you using? I am using b-ionic.
I will be following as I would like to see your results as well.