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Thread: DOS seting for a 20 gallon water change

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    DOS seting for a 20 gallon water change

    I would like to set DOS up to do a 20 gallon water change at the begining of the month and then again mid month. Can DOS do 20 gallon water changes on a single cycle? If so please advise how to program it to do this. Thanks.

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    It can do up to 30 gallons in a 24 hour period, but that defeats the entire purpose of having a DOS to make water parameters more consistent by doing continuous water changes. I would just tell it to dose 1.5-2 gallons per day and be done with it. If you are dead set on this type of approach, twice monthly is not possible, but weekly is by adding the derided dosing amount (10 gallons weekly) into the wizard over 24 hours and adding this line to the advanced tab (gear icon). This would do weekly dosing on Saturday.

    If DOW SMTWTF- Then OFF

    You might be an engineer if...You have no life and can prove it mathematically.

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    Quote Originally Posted by zombie View Post
    It can do up to 30 gallons in a 24 hour period, but that defeats the entire purpose of having a DOS to make water parameters more consistent by doing continuous water changes. I would just tell it to dose 1.5-2 gallons per day and be done with it. If you are dead set on this type of approach, twice monthly is not possible, but weekly is by adding the derided dosing amount (10 gallons weekly) into the wizard over 24 hours and adding this line to the advanced tab (gear icon). This would do weekly dosing on Saturday.

    If DOW SMTWTF- Then OFF

    You might be an engineer if...You have no life and can prove it mathematically.
    the problem with doing continuous water changes is that once you mix the salt into water Cal and Alk will precipitate out of solution if not used right away. so if you want to maintain Cal and alk on the high side of NSW than you should be using that saltwater right away in a water change.

    Please advise how to program do a 20 gallon water change?

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    Quote Originally Posted by coralsrmylife2016 View Post
    the problem with doing continuous water changes is that once you mix the salt into water Cal and Alk will precipitate out of solution if not used right away. so if you want to maintain Cal and alk on the high side of NSW than you should be using that saltwater right away in a water change.

    Please advise how to program do a 20 gallon water change?
    Where are you getting this information? I have had saltwater in storage for months in a covered barrel (no powerhead or heater) at 12 dKH, 500ppm calcium, and 1350 Mg and the levels did not change appreciably. I could see a little bit of precipitation occurring if you keep the water heated with a powerhead and have magnesium well below balanced levels but not when mixed properly and left cold.

    As I already said in the original Post, you can't do bi-monthly with a DOS. Once a week is the farthest you can go.

    You might be an engineer if...You have no life and can prove it mathematically.

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    Quote Originally Posted by zombie View Post
    Where are you getting this information? I have had saltwater in storage for months in a covered barrel (no powerhead or heater) at 12 dKH, 500ppm calcium, and 1350 Mg and the levels did not change appreciably. I could see a little bit of precipitation occurring if you keep the water heated with a powerhead and have magnesium well below balanced levels but not when mixed properly and left cold.

    As I already said in the original Post, you can't do bi-monthly with a DOS. Once a week is the farthest you can go.

    You might be an engineer if...You have no life and can prove it mathematically.
    I was speaking with my LFS and Randy Holmes Farley on Reef2Reef who both told me the same. I like to boost the levels on the high side and Randy said that is why salts like red sea pro want you to use the salt right away. However what you mention will slow the precipitation. Once you mis the salt you dont use a pump to keep the water moving? No need to do this? 8nteresting as i always thought you need to keep a pump moving water. I dont use a heater so it will be kept cold.

    Follow up to the programing question... in the weekly programing how do i specify the DOS to deliver say 10g every saturday at a given time? thanks in advance for all yoir help so far.

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    I use a powerhead at least overnight and shut it off the next time I go down to the basement and have verified salinity is good. Once fully mixed, continuing to mix just causes precipitation and doesn't help anymore.

    There is definately some gunk that builds up over time (mostly anticaking agent from reef crystals) but there is not appreciably more over the same time period when I use a lot vs next to none. Unfortunately I did not keep good logs of my test results from back when I tested it (This was before neptune made it easy), so I don't remember exactly how much it lost, but I know it was less than 1dKH over the course of like 2 months and Ca and Mg didn't change much at all. Maybe 20ppm. I would ask Randy what he thinks the precipitation rate actually is (I can test myself, but that will take a couple months), because I expect it is pretty low and there are multiple ways to account for it (add a little 2 part every weekend, or just bump the reactor/2 part up a tad and do continuous water change).



    You might be an engineer if...You have no life and can prove it mathematically.

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    Quote Originally Posted by zombie View Post
    I use a powerhead at least overnight and shut it off the next time I go down to the basement and have verified salinity is good. Once fully mixed, continuing to mix just causes precipitation and doesn't help anymore.

    There is definately some gunk that builds up over time (mostly anticaking agent from reef crystals) but there is not appreciably more over the same time period when I use a lot vs next to none. Unfortunately I did not keep good logs of my test results from back when I tested it (This was before neptune made it easy), so I don't remember exactly how much it lost, but I know it was less than 1dKH over the course of like 2 months and Ca and Mg didn't change much at all. Maybe 20ppm. I would ask Randy what he thinks the precipitation rate actually is (I can test myself, but that will take a couple months), because I expect it is pretty low and there are multiple ways to account for it (add a little 2 part every weekend, or just bump the reactor/2 part up a tad and do continuous water change).



    You might be an engineer if...You have no life and can prove it mathematically.
    thanks for the info. I am going to give it a try.
    '

    Follow up to the programing question... in the weekly programing how do i specify the DOS to deliver say 10g every saturday at a given time?

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    You put 10 gallons in the wizard (40000 ml) over a period of between 8 and 24 hours. The longer the timeframe the quieter it will be and the pump lifetime will be increased as well.

    In the advanced window add the line (this is for sunday)

    If DOW SMTWTF- Then OFF


    Plus any other failsafes you want such as low or high tank conductivity, low or high sump level, etc.



    You might be an engineer if...You have no life and can prove it mathematically.

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