Setting up doser for AFR

jadedog

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Good evening!

I've been manually dosing my all for reef dose daily at 8pm (12ml daily). I was wondering when I set up my doser should I just set it to dose 12ml at 8pm or should I space it out throughout the day like 4 doses that are 3ml? Does it matter I know AFR raises the alk slowly anyway so is this useless?
 

DarthRaiderBob

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Good evening!

I've been manually dosing my all for reef dose daily at 8pm (12ml daily). I was wondering when I set up my doser should I just set it to dose 12ml at 8pm or should I space it out throughout the day like 4 doses that are 3ml? Does it matter I know AFR raises the alk slowly anyway so is this useless?
I dose my tank 35ml daily, 15ml at 7 am and 20 ml at 7 pm. You could dose the same 6ml and 6 ml just to split it up throughout the day.
 

Gone Reefin’

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I use my doser to split up a few doses during daylight hours, front loaded a bit to the beginning of the photocycle. RHF has advised that this is a safer bet due to slight O2 depletion from the AFR (and O2 is naturally higher during daylight hours)
 

Fish Fan

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It doesn't matter much because of how slowly AFR works, but because AFR works through a bacterial process, it is *more correct* to dose it in the morning, an hour or two after lights on. This would allow photosynthetic organisms to start working and produce oxygen, which will counteract the oxygen that could potentially be rapidly consumed by the growth of bacteria the AFR causes.

I actually asked this same question when I started using AFR, and this thread I started may be of some help here too. I want to link to a reply from Randy Holmes-Farley who suggested that AFR can be added all at once, but he prefers to dose in the morning:

Good luck!
 

scotty333

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I don’t understand how your all not getting spikes
If I dosed the daily 70ml at once it would go from 7.7 - 9 and probably bleach my reef
I seem to be one of few that dose hourly over 24 hours
I think Randy aka “ the boss” told me afr converts to kh more rapidly in mature systems because there’s more of the bacteria to do it so how does a an all in one shot act as a time release ?
 

Randy Holmes-Farley

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I dose AFR in the morning. If you are dosing a large amount (more than 1 dKH per day) it may be worth spreading it out over the light part of the day, but AFR naturally spreads out its conversion into usable alk, so is not nearly so
Important to spread out as pure alk forms such as bicarbonate or carbonate or hydroxide.
 

Randy Holmes-Farley

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I don’t understand how your all not getting spikes
If I dosed the daily 70ml at once it would go from 7.7 - 9 and probably bleach my reef
I seem to be one of few that dose hourly over 24 hours
I think Randy aka “ the boss” told me afr converts to kh more rapidly in mature systems because there’s more of the bacteria to do it so how does a an all in one shot act as a time release ?

Do you regularly dose 70 mL?

How long do you see the conversion take?
 

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