Dosing start up

Discussion in 'Chemistry' started by LJC6780, Jul 26, 2017.

  1. LJC6780

    LJC6780 Grouper

    I just ordered a Hanna Alk tester because it was on sale and I was wanting to make testing easier and be more precise. Anyway ... first test read Alk at 5.83 dKH! :eek: So I started by adding some of the premix Alk solution that was in a tank stuff box ... I looked up on BRS to see how much I needed to get it up to 9 and it was over 7 ounces. I added about 20ml yesterday and I've added about 40ml today ... that's only 2oz by I know I don't need to increase it too quickly. I'll run all of the testing again today just to see where everything stands but it looks like I may need to start dosing Alk since it's been trending down lately.

    I have a dosing pump but have never used it. It's a bubble magus. How should I go about getting started? I have not looked recently but I'm pretty sure everything is in the box but any pointers or beginning dosing would be very helpful! It's an 85 gallon tank with roughly 15 gallons in the sump ... I always think of it as 100 gal volume but it's probably really 80-90 with rock and all ...
     
    Last edited: Jul 26, 2017
  2. huntindoc

    huntindoc RRMAS BOD Membership Director Staff Member

    When you say "premix Alk solution that was in a tank stuff box" what exactly is it? The BRS calculator is for their 2 part alkalinity mix (made from 2 cups of soda ash in 1 gallon of water). Not all solutions are the same. Some are MUCH more concentrated.

    I got about 6 oz when I used the calculator but I was using 80 gallon total water volume.

    You definitely want to go slowly although corals seem to better handle shifts up rather than down. It should take you a week or more to raise it that much. Dose a small amount, retest and repeat until you get where you want it. I would not raise it more than .6dKh or so a day.

    Where is your magnesium now? If it's still way low you need to correct that first. You probably will need to dose some calcium as well.
     
  3. LJC6780

    LJC6780 Grouper

    Yes, the BRS 2 part Alk mix. And when I say tank stuff ... it's just a box of dosing stuff and random testing supplies and parts.

    I'm about to test everything. I also need to recalibrate my probes (not my only means of testing) and just received the solutions from BRS.

    Magnesium has been trending upward.
     
  4. huntindoc

    huntindoc RRMAS BOD Membership Director Staff Member

    Probes? Salinity, ORP, Temp and pH are the only ones I know that you can get. If they have one for Alk/Ca/Mg and I didn't know it I'm fittin' to be mad! :D

    As long your Mg is above 1300 you should be able to get your alk/ca stable.

    I have BRS dosing pumps that I control with Apex. I'm sure the Bubble Magus has it's own controller. I would set it up to dose evenly as many times during the day as possible. I dose alkalinity at the top of the hour 24/7 and calcium at the bottom of the hour to avoid precipitation.

    What I would do is dose a small amount manually then start your dosing pump. Check after manually dosing and see where your starting point is. Then check 24 hours later. If it's the same you've found your alkalinity usage. If not turn the pump up a little and increase the doser.....so on and so forth.
     
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  5. LJC6780

    LJC6780 Grouper

    You are correct on the probes. Was just thinking about testing everything and needing to clean and calibrate the probes too ... my head is a little frazzled lately.

    Here are my results after approx 20 gallon water change. I figured clean water can't hurt whatever is going on ...

    IMG_3366.PNG
    SG is 1.025. pH 8.2. I have API and Salifert Calc tests and decided to see how they compared. Phos is Hanna ULR, nitrate and Mag are Salifert and Alk is the Hanna ppm all converted to normal readings in Apex.

    On a positive, nitrates are FINALLY coming down to a much more manageable range and I haven't even used the nitrate pearls yet.

    Guess I'll go get the doser out and see about getting it set up.

    Still gotta clean and calibrate!
     
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  6. LJC6780

    LJC6780 Grouper

    So I got out the pump and there are no instructions and only 2 sets of tubing. I'm guessing Alk and mag since calc seems to hold steadier ...
     
  7. huntindoc

    huntindoc RRMAS BOD Membership Director Staff Member

    Salifert is usually a little low on Mg....at least mine always is, so I bet you're close to being ok. Although I like to keep mine around 1400 it's not really necessary. That's about the right amount of increase....about 1dKh over two days, right? That phosphate is a little surprising with the nitrate being 10. Are you running GFO? If so I would turn it off for a while. Nitrate export will slow down without a little phosphate.
     
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  8. Botheboss

    Botheboss Director-At Large

    I thought I herd Hanna alk tester wasn't the most accurate. Might want to look into that.
     
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  9. LJC6780

    LJC6780 Grouper

    Yes I've been running GFO and actually was a little surprised to see it at zero since I believe it was up to 0.06 not too long ago. I removed it tonight because it wasn't flowing right so I pulled it to clean the hoses and pump and just make sure it was all ok.

    Is it ok to just turn it off but leave it on the tank or will that make toxic water conditions inside the chamber? Could I set it to run every other day or something like that?

    I did add some denitrifying bacteria soaked marine pure balls to the return chamber of the sump a while back and I'm hoping that is what is finally getting these nitrates down. Believe it or not I think I read the test at 80 at one point. It's been between 20-50 lately so I was a bit surprised to see it at 10 and I even checked against the low range and it read the same.

    I hadn't heard that the Hanna Alk tester wasn't very accurate ... I'll test against API tomorrow. I think that's the only other test I have on hand.
     
  10. huntindoc

    huntindoc RRMAS BOD Membership Director Staff Member

    I would just pull the GFO until the phosphates are back up to about 0.06 or greater. You will figure out how much to put in the reactor to keep it in the sweet spot.

    Good job on the nitrates. 10 really isn't bad, lots of people like to keep theirs there.

    Hanna had some reagent issues about a year ago but that has been resolved. Who knows about accuracy because unless you're checking it with a reference lab there is no way to know about the accuracy. What's important in a hobby kit is consistency and Hanna is very consistent. Actually API has the worst reputation of any of the test kits for precision (consistency) IMO. I think Salifert for dKh is also good but doesn't have the resolution that Hanna does.

    This is the last 3 weeks of my Alk readings.

    [​IMG]
     
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  11. LJC6780

    LJC6780 Grouper

    I like the Hanna because it gives you a definitive reading and you don't have to guess at what color it matches on a card, that may or may not be the same color as the card in the next test ... I'd love to eventually have a Hanna checker for everything. And as far as their margin of error ... is that a range for each individual test, each individual tester unit or the lot of reagent? Like can it be +5% on one test and -3% on the next? Just curious about the consistency thing ... like is it consistently at one point in the range?
     
  12. huntindoc

    huntindoc RRMAS BOD Membership Director Staff Member

    The +/- 5% has to do with accuracy. In other words if your ppm PO4 reads 20 ppm it could be anywhere from 19-21. Precision means if you test the same water several times it will read the same each time. This is what is important for hobbyist. That way we can track trends which is more important than absolute numbers. If you know where your tank does well, then you can monitor and keep it there.

    Right now the only Hanna checkers that I would recommend are the ULR phosphorous and the alkalinity. Their calcium checker has a poor reputation and the Salifert for calcium is very good and easy to do. Nitrate I use either Salifert or Red Sea.
     
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  13. LJC6780

    LJC6780 Grouper

    Yes, my question is does the accuracy refer to the meter itself, each individual test round or to the lot of reagent used? Like if I use the same lot of reagent from one test to the next and the same meter, will my margin of error be the same? Like always +5% ? Or can it fluctuate between the high and low margin from test to test?

    Like if my numbers are fluctuating, do I consider that actual numbers fluctuating because I'm using the same checker or same reagent or do I consider that a possible change in margin of error and my numbers could actually be holding steady?

    Does that make more sense of what I'm asking?
     
  14. LJC6780

    LJC6780 Grouper

    Also I finally got my probes cleaned and calibrated. Went ahead and calibrated my pH meter and refractometer. Cond probe reading spot on according to the solution and a salinity/SG conversion program I found online. Somehow all of the sudden my SG is down to 1.0224 (sal 29.7) and I've been keeping it around 1.025-1.0255 (sal 33.2-33.8). It read 29.9 after getting all set up and I even added about 1/2c salt mixed into about 1c RODI water to try to bring it up a bit (slowly added to return pump chamber to be mixed well) and it seemed to go down instead.

    Can adding alk and mag change how salinity is read? Temp has been holding steady at 76-77.

    I set up the doser yesterday evening and set it to dose 45ml of Alk over 12 hours starting 1 hour before lights off and ending 1 hour after lights on (approx.) and dosing 24ml of mag over 24 hours. It automatically adds the time and you can adjust hours but not minutes (that I can tell.) so mag doses on the hour and alk on :05. I guess pump 3 doses on the :10 but I don't have anything on it at the moment.

    Since I set it up later in the day I'll wait to test again until later this afternoon to see if everything is moving to where I want it.

    As of yesterday evening:
    IMG_3389.PNG
    Oh and that latest calc test was salifert and I didn't dose any calc in between.
     
  15. LJC6780

    LJC6780 Grouper

    Ok so after testing with my refractometer I added a bit more salt mix to get to 1.0255-1.026. Oddly, the probe stayed at 29.8. I jiggled it around and rinsed it and put it back and it consistently reads 31.4 now. But that's still too low! Last night it tested perfectly. Does this mean it's going out and I have to get a new probe? Is there anything I can do to bring it back? I did soak in vinegar water and clean with a tooth brush like the instructions say but I didn't soak it for hours. Should I try that and recalibrate?
     
  16. huntindoc

    huntindoc RRMAS BOD Membership Director Staff Member

    Can it not be calibrated with a known salinity sample (like the pH probe can)?

    I don't think I would depend on a hobby grade salinity probe. I've not heard good things about their reliability. Way to easy to calibrate an inexpensive refractometer and be spot on. I do think it would be good to monitor trends to alert you to a change so you can check with the refractometer.

    The one thing in my tank that never seems to change is salinity. If you're not putting any extra salt in or taking any out (water change salinity same as tank) there really is only one way it can change.......rising due to 2 part dosing.
     
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  17. LJC6780

    LJC6780 Grouper

    No, not relying on it but using it to monitor ... it always read a little off but then jumped up to like 47 or something crazy. I finally ordered the calibration solutions and got everything done. Not sure which probe it is ... Kevin was one to buy top of the line equipment. I'll have to see if I can figure it out.

    Water changes test the same ... I think where I may have gone wrong is I had to replace the pump in my ATO and have been topping off manually lately and since I moved the sensor to allow more water over the return pump, I haven't made new lines on the sump and was just eyeballing ... guess I eyeballed wrong! Got the new pump put in last night though.

    I also looked up the calcium dose since calc is a little low for me. No matter which solution I chose it came back for many ounces to be dosed just to change it by 50ppm so I dosed about 3oz (not near the Alk) and will test today to see how much it went up. I'm not exactly sure which calc solution I have since there were a couple things in the box but it was mixed in the clear jug like the other two.

    Thankfully there wasn't much of anything already mixed so I'll be able to make up new batches and know exactly what I've got and how it was mixed.
     
  18. LJC6780

    LJC6780 Grouper

    Well it looks like everything is back in normal range ... I'm wondering if I should continue dosing at the same rate (probably not), back off some (possibly?), or turn it off and see where it goes over the next few days ...

    IMG_3413.PNG
     
  19. huntindoc

    huntindoc RRMAS BOD Membership Director Staff Member

    If you're parameters are rising you will definitely need to decrease the dosing. Your alkalinity has been rising about 0.8 dKh per day pretty consistently. I would lower your dosing by say 30% and see what it does in 24 hours. Continue to adjust till it stays the same. Same principle for the Calcium but it looks like you are dosing a lot more than demand compared to alkalinity (so I would reduce the dosing even more than alkalinity).
     
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  20. LJC6780

    LJC6780 Grouper

    I just manually dosed the calc since it usually just remains steady ... but I only dosed about 3-4 oz and the BRS calculator said something like 15oz was needed to raise to 460. So I don't know what's going on there.

    I actually didn't do anything last night, but the Alk has only been dosing over night so I'll test and adjust today and see what happens tonight. I think it's set for 3ml/hr for 12 hours. I could back it down to 2 and see what happens.

    The mag is the only one that has been dosing 24 hours. I think it is set to dose 2ml/hr. Didn't raise at all with 1ml ... actually fell. Something I've added recently seems to be sucking up magnesium! I'll see where it is tonight and see if dosing something like 36ml/24hr will do the job.
     

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