Established tank w/ some out of whack chemistry for a while and would like some help getting things back on the right path.

[Greenstarfish03]

Hello,

I have a several year old tank that has always been pretty stable w/ a mixed reef mostly softies and LPS's, and one SPS. All seems healthy currently, but a few months ago I switched to a new Apex from my RK and I've added a new BRS dosing pump for CA. I also switched from @Randy Holmes-Farley 2 part recipe #2 to recipe #1 b/c my PH seemed to run around 8.2 or 8.3 so I figured if the other recipe is more concentrated then I would have to dose less and it would be easier. I also never really manager MG and I decided to get that in line as well and I created an issue. My test kit was old and no matter what I did it said the MG was low so I kept using Randy's calculator to add more MG. Eventually I said this is odd and I ordered a new red sea test kit and an ICP mail in kit. To make a long story short all of my standard parameters are perfect except the following:

Current parameters:
MG - 1600 (this has actually came down from 1800 a couple months ago confirmed by the ICP test)
CA - 270 (Over the last month or so the CA has drifted down even if I dose extra, but I assume that is b/c the ALK is a little high)
ALK - 11.2 (its held here fro the last month plus)
PH - ranges from 8.48 at night to 8.61 during the day and has been creeping up over the last month (really since I switched to recipe #2)
Salinity - 1.026

Here is my dosing program for ALK on my Apex:

Fallback OFF
OSC 000:00/004:30/055:30 Then ON
If pH > 8.59 Then OFF

My PH has often lately been hitting the 8.59 limit and irritating me. Then it doesn't dose which seems fine b/c my ALK is stable but high. I would like to get the ALK down a little maybe between 9 and 10 and get the PH at a point where its not constantly bumping into my limit. I would love the MG to come down too but I have probably done 5 water changes since the ICP test and its still at 1600 so I'm not sure what to do about that. The tank overall looks fine everything is healthy I just fell like I'm walking a fine line and I would like to get things a little more in the center of their ranges slowly.

Let me know if you need anything or I left anything out.

Thanks for your pointers.

 

[ShadowReef]

Alk, calc and magnesium are all related and affect each other. Your calcium is likely a result of the magnesium being out of whack, your alkalinity is fine. Lots of people run at that and above. But I would def want that calcium level higher. Unfortunately the only way I know of getting that magnesium down is water changes. How much are you changing? Are you using a salt that has high concentrations of magnesium, perhaps that's why it's not dropping as quickly?

Is there anything else you're adding that contains magnesium in any form? The good news is it's going down, and doing it slowly isnt a bad thing.

 

[Randy Holmes-Farley]

Alk, calc and magnesium are all related and affect each other. Your calcium is likely a result of the magnesium being out of whack,

Sorry, but that cannot be. There's no mechanism for magnesium at any level high or low causing calcium issues and not alk issues.

 

[Randy Holmes-Farley]

Hello,

I have a several year old tank that has always been pretty stable w/ a mixed reef mostly softies and LPS's, and one SPS. All seems healthy currently, but a few months ago I switched to a new Apex from my RK and I've added a new BRS dosing pump for CA. I also switched from @Randy Holmes-Farley 2 part recipe #2 to recipe #1 b/c my PH seemed to run around 8.2 or 8.3 so I figured if the other recipe is more concentrated then I would have to dose less and it would be easier. I also never really manager MG and I decided to get that in line as well and I created an issue. My test kit was old and no matter what I did it said the MG was low so I kept using Randy's calculator to add more MG. Eventually I said this is odd and I ordered a new red sea test kit and an ICP mail in kit. To make a long story short all of my standard parameters are perfect except the following:

Current parameters:
MG - 1600 (this has actually came down from 1800 a couple months ago confirmed by the ICP test)
CA - 270 (Over the last month or so the CA has drifted down even if I dose extra, but I assume that is b/c the ALK is a little high)
ALK - 11.2 (its held here fro the last month plus)
PH - ranges from 8.48 at night to 8.61 during the day and has been creeping up over the last month (really since I switched to recipe #2)
Salinity - 1.026

Here is my dosing program for ALK on my Apex:

Fallback OFF
OSC 000:00/004:30/055:30 Then ON
If pH > 8.59 Then OFF

My PH has often lately been hitting the 8.59 limit and irritating me. Then it doesn't dose which seems fine b/c my ALK is stable but high. I would like to get the ALK down a little maybe between 9 and 10 and get the PH at a point where its not constantly bumping into my limit. I would love the MG to come down too but I have probably done 5 water changes since the ICP test and its still at 1600 so I'm not sure what to do about that. The tank overall looks fine everything is healthy I just fell like I'm walking a fine line and I would like to get things a little more in the center of their ranges slowly.

Let me know if you need anything or I left anything out.

Thanks for your pointers.

IF you are confident the in the calcium test (I'm suspicious, try it on some new salt water), then the answer is boost calcium manually with just the calcium part. Then use both alk and calcium equally to maintain alk where you want it and watch calcium over time to see if deviations are needed.

 

[Greenstarfish03]

Alk, calc and magnesium are all related and affect each other. Your calcium is likely a result of the magnesium being out of whack, your alkalinity is fine. Lots of people run at that and above. But I would def want that calcium level higher. Unfortunately the only way I know of getting that magnesium down is water changes. How much are you changing? Are you using a salt that has high concentrations of magnesium, perhaps that's why it's not dropping as quickly?

Is there anything else you're adding that contains magnesium in any form? The good news is it's going down, and doing it slowly isnt a bad thing.

Thanks for replying. I appreciate the help. Ive been doing this a long time but ive not always done things right. my tank is 100g and i routinely change 30g once a month, but the last 2 months ive probably done 4 to try to bring the mg down. For salt i have used basic instant ocean salt for many years. I will try to test my next batch of salt water before my water change to see the levels of my mix. Its lrobably food to know. I add very little to my tank. I do add a couple caps of acropower a week and for the last few weeks i've added a cap of vibrant a week bc i have some bubble algae in some stubborn places. Really my biggest concern is my ph. I know its not terribly high but i woukd like it to run a little lower. I feel like im walking a fine line. As far as the mg goes it doesnt seem to be hurting anything and like u said its comming down slowly. I am having a problem keeping my ca up so figuring out why that is would be helpfull.

 

[Randy Holmes-Farley]

For salt i have used basic instant ocean salt for many years. I will try to test my next batch of salt water before my water change to see the levels of my mix. Its lrobably food to know. I add very little to my tank.

The purpose of that suggestion (at least when I made it) is not to see the levels in the new IO, which are almost certainly fine, but to see if your calcium kit is giving reliable answers. Test kit issues are common.

 

[ShadowReef]

Thanks for replying. I appreciate the help. Ive been doing this a long time but ive not always done things right. my tank is 100g and i routinely change 30g once a month, but the last 2 months ive probably done 4 to try to bring the mg down. For salt i have used basic instant ocean salt for many years. I will try to test my next batch of salt water before my water change to see the levels of my mix. Its lrobably food to know. I add very little to my tank. I do add a couple caps of acropower a week and for the last few weeks i've added a cap of vibrant a week bc i have some bubble algae in some stubborn places. Really my biggest concern is my ph. I know its not terribly high but i woukd like it to run a little lower. I feel like im walking a fine line. As far as the mg goes it doesnt seem to be hurting anything and like u said its comming down slowly. I am having a problem keeping my ca up so figuring out why that is would be helpfull.

Apologies I misread your post, I thought your alk was 8. something but that was your ph. It is a bit high but I still wouldnt be too worried by that. Maybe slow down your alk dosing and increase your calcium dosing but keep testing daily so you dont have a sudden low alk issue (preferably at the same time of the day), magnesium will lower with water changes. It would be a good idea to record how much of a drop in alkalinity and increase in calcium you are getting daily so you can keep adjusting until you get to the level you want. From there you should be able to figure out what your tank actually uses in a day so you can dose for stability going forward.

 

[Greenstarfish03]

IF you are confident the in the calcium test (I'm suspicious, try it on some new salt water), then the answer is boost calcium manually with just the calcium part. Then use both alk and calcium equally to maintain alk where you want it and watch calcium over time to see if deviations are needed.

Thanks for responding @Randy Holmes. I have had some of your old articles on reefkeeping.com saved for a long time. They are my goto for this stuff. I will admit though i don't always understand the details To answer your questions the CA test is a fairly new red sea kit. I think its right but i wouldnt rule anything out 100%. I just got a new ICP mail in kit so I plan to test everything at home then take a sample from my rodi water and my tank water the same day for analysis. Then i guess i can rule out testing errors. I run two dossing pumps from 5 gallon buckets based on your 2 part recipes then i always have a 1 gallon jug of what i call ca and mg dose. I clearly dont use the mg die anymore. I make the dose from one of the calculators tou recommend. With that being said i didnt write down the cocnetration of the last ca dose i made so i have forgotten its strength which i know sounds bad. 5 days ago i dosed 2 extra cups of ca dose and retested a day later and the ca didnt change at all which is very abnormal. I probably need to make a new batch of ca dose then i can try to raiae the ca again. I have been dosing roughly equal parts ca and alk for yeara now. I find that is harding then it sounds though bc the brs dosing pumps i use say they dispense the same amount but i found that they dont so i have to set both timers a little different to comoenstate but that is my goal. I have always used recipe but changed to recipe 1 a few months ago and since my ph has creeped up so i just switched back to recipe 2. Do uou have any thoughts on my PH levels? It seems to be creeping up slowly and its now rynning between 8.4ish at night to 8.61 or so during the day but has had a define upward tren over the last few months. Do you thinking switching back to recipe 2 will help bring that down? Or should i not worry about that?

I appreciate your feedback. I didnt ecen know you pisted on this forum until recently and like i said i used your older articles as the fold standard for reef chemistry. Thanks for all your detailed information you have posted over the years.

 

[ShadowReef]

Sorry, but that cannot be. There's no mechanism for magnesium at any level high or low causing calcium issues and not alk issues.

Yeah I read the post wrong, I agree that it would affect both, which is what I meant by them all being connected. Hence if 2 variables arent where they should be then there is a connection. In this case, the alk is higher than it has been so as you correctly pointed out there would be (and is) alk issues