Alk difference in one day?

[purplereef]

Hi guys,
I am confused as to why this isn't causing more problems in my tank. I have a stand alone GHL doser and I run my dosings at night when the PH is low. I start dosing my Alk at 9:00pm and then have it alternate every other hour with my calcium till 6:00am. So my dosing is as follows.....
9:00pm 10ml's Alk
10:00pm 10ml's Cal
11:00pm 10ml's Alk
12:00am 10ml's Cal
1:00am 10ml's Alk
2:00am 10ml's Cal
3:00am 10ml's Alk
4:00am 10ml's Cal
5:00am 10ml's Alk
6:00am 10ml's Cal
I have 150 gallons of total water volume in my system.
I use a Lemotte Alk test kit and these are my readings....
6:30am 8.77
8:10pm 7.93
My corals look great except for the new growth on a few acros looks very thin branched. Do you think I should be concerned about my Alkalinity differences? I was told a long time ago that any difference of .4 in Alk would really hurt corals. Dan.

 

[this is me]

50ml of AlK in 150gal with acro? I'm using almost 80ml in my 55gallon with just aneomnes! ALK is being used all the time even by coraline algae. You have to bump the ml up and also dose during the day. There's no reason why calcium is being dosed at night. I would just do auto dosage and specify the amount of calcium you wish. Manually dose ALK every hour or 30mins at night at also every 2-3 hours during the day. You will have to play with the amount until your desired level is reached.
Have you tested your calcium level? It might be imbalance or low as well.

 

[doggydoc]

50ml of AlK in 150gal with acro? I'm using almost 80ml in my 55gallon with just aneomnes! ALK is being used all the time even by coraline algae. You have to bump the ml up and also dose during the day. There's no reason why calcium is being dosed at night. I would just do auto dosage and specify the amount of calcium you wish. Manually dose ALK every hour or 30mins at night at also every 2-3 hours during the day. You will have to play with the amount until your desired level is reached.
Have you tested your calcium level? It might be imbalance or low as well.

+ 1

I am dosing almost the same amount and I have a 60 gallon cube.
I would test Ca AND alk, and prob get a second test kit to verify.

 

[purplereef]

I guess I have a very low demand maybe? I just checked my calcium and it is 450 using a Salifert test kit. I am bare bottom and I have a small amount of live rock. I have coralline growing all over the bottom and on the rock. I was told it was very bad to split up the dosings into very small amounts due to possible error by the doser. I agree dosing around the clock will stop the changes in Alk, but what do I do dose 1ml at a time? Thanks.

 

[doggydoc]

I dose alk mostly at night manually. My dosing amount varies but I am dosing close to 50 ml daily. I do dose during the day also, but minimal amounts.
Also WHERE do you have your ph probe located? Have you done calibration?
If your dosing at night, and the ph probe is very close to the dosing tube you might get higher readings.



Always at sea;
Doggydoc

 

[this is me]

I guess I have a very low demand maybe? I just checked my calcium and it is 450 using a Salifert test kit. I am bare bottom and I have a small amount of live rock. I have coralline growing all over the bottom and on the rock. I was told it was very bad to split up the dosings into very small amounts due to possible error by the doser. I agree dosing around the clock will stop the changes in Alk, but what do I do dose 1ml at a time? Thanks.

Have you calibrated your doser pump? You can get it to almost the exact amount you set it at.
Set a manual dosage say 10ml a minute before the actual time. Then have a test tube to collect the amount being dispense. If it's not 10ml, turn down your pump rate speed. Say start with 60ml/min down to 55ml/min. Do this to all the dosing pumps.

1ml at a time won't do you any good in that size tank. I would start with 10ml every hour at night and 5ml every two hours during the day. It does take a couple try to get it the right amount with the desired level. Just like a calcium reactor. What level you want to keep your tank at? Find out that level and use the 2-part calculator on BRS and add that amount to your current amount. The total amount will be what's needed in the 24hr dosage. You can chop this amount into pieces and bits and dose anytime you like.

 

[purplereef]

Thank you Nick. I would like to keep my Alk around 8.0. I also don't run GFO or even carbon at this time. So could you please give me a dosing schedule? Like x amount of Alk at say 6:00am etc. If we start out at 60ml's of each part then I don't think I will nuke my tank. So calcium I can just enter automatic and dose 60mls correct? For Alk can you break it up for me when I should dose and how much? Thanks Nick, Dan.

 

[purplereef]

I should add the fact that I have calibrated my doser and I have it set to pump out 12ml's and I continually get 10ml's from the two pumps I use on my 3 pump SA doser.

 

[this is me]

Dan,
You can chop that 60-70ml into how many block you want. I don't know the nature of how your system is set up so I'm afraid to give you a schedule. For example, I don't know your lighting schedule or if run a reverse lighting cycle or not. The main reason to dose ALK at night is to raise the PH up in the absence of light.
I dose every hour after 2 hours my lights have been off. I also run a reverse lighting period in my refugium(refugium is off during the day and on at light).

 

[purplereef]

Okay I understand. My T5 lights come on at 9:00am and off at 7:00pm. My halides come on at 11:00am and off at 6:00pm. I don't run any other lights. I really need to recalibrate the doser. I was using a crummy shot glass with measurments on it to calibrate the doser. I don't think it was the most accurate thing in the world to use. So if I put the calcium on automatic it will dose 3ml's 20 timesduring a 24 hour period correct?

 

[this is me]

Yes.

 

[purplereef]

Hi Nick,
I put the calcium on Automatic but I have yet to see it dose. When does it dose? I have been watching around the top of every hour but I haven't seen it dose yet. I set it to dose 20 times at 3ml's.

 

[this is me]

I can't tell when exactly mine is dosing either. But I do see it dose sometime. If you are really concern, you can put a flask and collect the chemical being dosed for 24hr to see if that's what you set it at. For me, I just look at my solution reservoir to see it goes down each day.

 

[purplereef]

Hi Nick,
So I got my numbers a little closer together now. Here is my dosing schedule.
1am 5ml's
2am 5ml's
3am 5ml's
4am 5ml's
6am 5ml's
7am 10ml's
12pm 10ml's
3pm 10ml's
9pm 5ml's
10pm 5ml's
11pm 5ml's
With my Lemotte test kit I got the following readings....
7.82 at 8:20pm
8.32 at 8:45am
I would like to tighten up the numbers even more. How do you think I should change my numbers? Also my calcium is on Auto dosing 4ml's 20 times a day. Dan

 

[this is me]

Hi Dan,
I think those numbers are pretty good. There will be some differences with AlK level with manually dosing. I don't think half a KH would makes a difference.
If you want you can break the 10ml even further. Remember not only you can AND the inputs but you can AND the the gates as well. So you can have as many scheduled dosing time as you want.
Personally, I would sweat it.

If you want less swing on your level, just use the auto dosing with small amount at many times a day.

 

[purplereef]

Thank you very much Nick.

 

[this is me]

Hi Dan,
Remember not only you can AND the inputs but you can AND the the gates as well. So you can have as many scheduled dosing time as you want.

Hi Dan,
I made a mistake here. You want to use the OR gate if you want to combine the timers together not AND.

 

[purplereef]

Thank you Nick. I have the stand alone doser so it doesn't use any of these terms for programming. The stand alone doser is very user friendly and I am really glad I got it.