Rinsing food

Wonkabar

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So I have been rinsing my food for a little while now. I recently started using the AF4 frozen feeder and I’m wondering what the best way to keep the food from going bad is. since I’m getting the frozen food, defrosting it in order to rinse it, then refreeze it, then leaving it defrosted/thawed/still cold enough In the feeder. Does anyone have any ideas on a better method?
 

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Not sure how the AF4 works... does it use defrosted food only?
 

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While I often rinse frozen food to reduce the PO₄ spike after feeding, it doesn't remove too much of the overall PO₄. In an experiment proposed by JonasRoman, we found that only approx. 1.6% - 5% of the total phosphate in the tested frozen food was removed by rinsing it (don't get confused by the initially found 60%, and check my reply which reproduces the results and fixes a small error in the initial calculations). Most phosphate is still bound to the organic matter and can't be rinsed away. In other words: If you can live with 5% more phosphate, it probably won't matter :)
 
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Wonkabar

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While I often rinse frozen food to reduce the PO₄ spike after feeding, it doesn't remove too much of the overall PO₄. In an experiment proposed by JonasRoman, we found that only approx. 1.6% - 5% of the total phosphate in the tested frozen food was removed by rinsing it (don't get confused by the initially found 60%, and check my reply which reproduces the results and fixes a small error in the initial calculations). Most phosphate is still bound to the organic matter and can't be rinsed away. In other words: If you can live with 5% more phosphate, it probably won't matter :)
Thank you for this. Even though you still gave me the tldr I went ahead and read the thread and your reply anyway. My hunch is rinsing is a lot of work for a minimal reward. I don’t think that a 5% increase is making that big of a difference especially with my weekly water changes.
 

EnterName

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While I often rinse frozen food to reduce the PO₄ spike after feeding, it doesn't remove too much of the overall PO₄. In an experiment proposed by JonasRoman, we found that only approx. 1.6% - 5% of the total phosphate in the tested frozen food was removed by rinsing it (don't get confused by the initially found 60%, and check my reply which reproduces the results and fixes a small error in the initial calculations). Most phosphate is still bound to the organic matter and can't be rinsed away. In other words: If you can live with 5% more phosphate, it probably won't matter :)
Thank you for this. Even though you still gave me the tldr I went ahead and read the thread and your reply anyway. My hunch is rinsing is a lot of work for a minimal reward. I don’t think that a 5% increase is making that big of a difference especially with my weekly water changes.
To be fair, the sample size is 2 and we only looked at brine shrimp, but it would be really weird if a significant portion of phosphates that were previously bound to organic matter suddenly became soluble in water and could be flushed away.

Maybe I should add other frozen food types to the study... Might try it tomorrow or so.
 
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Wonkabar

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While I often rinse frozen food to reduce the PO₄ spike after feeding, it doesn't remove too much of the overall PO₄. In an experiment proposed by JonasRoman, we found that only approx. 1.6% - 5% of the total phosphate in the tested frozen food was removed by rinsing it (don't get confused by the initially found 60%, and check my reply which reproduces the results and fixes a small error in the initial calculations). Most phosphate is still bound to the organic matter and can't be rinsed away. In other words: If you can live with 5% more phosphate, it probably won't matter :)
Thank you for this. Even though you still gave me the tldr I went ahead and read the thread and your reply anyway. My hunch is rinsing is a lot of work for a minimal reward. I don’t think that a 5% increase is making that big of a difference especially with my weekly water changes.
To be fair, the sample size is 2 and we only looked at brine shrimp, but it would be really weird if a significant portion of phosphates that were previously bound to organic matter suddenly became soluble in water and could be flushed away.

Maybe I should add other frozen food types to the study... Might try it tomorrow or so.
If you do I would be very interested in the results.
 

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So I have been rinsing my food for a little while now. I recently started using the AF4 frozen feeder and I’m wondering what the best way to keep the food from going bad is. since I’m getting the frozen food, defrosting it in order to rinse it, then refreeze it, then leaving it defrosted/thawed/still cold enough In the feeder. Does anyone have any ideas on a better method?
I have an AF4. I feed 3.5 cubes of frozen a day (along with some pellets and nori). Before the AF4 I rinsed, also as part of an effort to to reduce particulates and phosphate. I did not rinse the first 10 days I had the AF4 and did notice a bump in phosphate (I have tested phosphate 5 times or so in the last week). I have subsequently switched back to rinsing and phosphates went down.

What I do is thaw then rinse 1 week of frozen food (2 weeks if I am gone for longer). I then add high salinity water. Specifically 1.050sg water which is double the salinity of the tank. I add enough high salinity water to bring the water level to the level where I can do the target amount of feedings. For example, if I want to do two 5ml feedings for 14 days then I fill the container to the 140ml line. I also run the machine on the coldest setting the high salinity water helps the slurry stay liquid rather than frozen.

I have not been using the AF4 long but the method described above seems to be working so far. I smelled the slurry yesterday (day 5) and smelled nothing (no detectable decomposition) and was still liquid. I assume rinsing out the fines and reducing the phosphate level in the liquid portion of the slurry helps with preservation.

For reference my phosphates are typically 0.05ppm and nitrates very low (I have to dose to ensure they don’t go to zero). I feed 3.5 cubes of frozen, 3 feedings of pellet, and one sheet of nori a day. I also feed 1-2 clams to my Copperhand and a cube of frozen to my scoly every week. My fish are fat but nutrients on the low side.
 
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slingfox

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.2-.3 right now
I would bet if you don’t rinse your phosphates will go higher with the AF4. At least that is what happened to me, but my starting phosphates was 0.05ppm. During the first week running the AF4 I retained phosphates around five times :)
 
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Wonkabar

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So I have been rinsing my food for a little while now. I recently started using the AF4 frozen feeder and I’m wondering what the best way to keep the food from going bad is. since I’m getting the frozen food, defrosting it in order to rinse it, then refreeze it, then leaving it defrosted/thawed/still cold enough In the feeder. Does anyone have any ideas on a better method?
I have an AF4. I feed 3.5 cubes of frozen a day (along with some pellets and nori). Before the AF4 I rinsed, also as part of an effort to to reduce particulates and phosphate. I did not rinse the first 10 days I had the AF4 and did notice a bump in phosphate. I have subsequently switched back to rinsing and phosphates went down.

What I do is thaw then rinse 1 week of frozen food (2 weeks if I am gone for longer). I then add high salinity water. Specifically 1.050sg water which is double the salinity of the tank. I add enough high salinity water to bring the water level to the level where I can do the target amount of feedings. For example, if I want to do two 5ml feedings for 14 days then I fill the container to the 140ml line. I also run the machine on the coldest setting the high salinity water helps the slurry stay liquid rather than frozen.

I have not been using the AF4 long but the method described above seems to be working so far. I smelled the slurry yesterday (day 5) and was still liquid. I assume rinsing out the fines and reducing the phosphate level in the liquid portion of the slurry helps with preservation modestly.

For reference my phosphates are typically 0.05ppm and nitrates very low (I have to dose to ensure they don’t go to zero). I feed 3.5 cubes of frozen, 3 feedings of pellet, and one sheet of nori a day. I also feed 1-2 clams to my Copperhand and a cube of frozen to my scoly every week. My fish are fat but nutrients on the low side.
Thank you for such a thorough detailed response. I think I’m going to mix higher salinity water specifically for the af4 and do the same as you. I smelled the food yesterday after 10 days on the second coldest setting and it definitely didn’t smell great. I have about 40 fish in my tank and some of them would be very difficult to replace. I definitely don’t want to feed them rotten food.
 
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Wonkabar

Wonkabar

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I would bet if you don’t rinse your phosphates will go higher with the AF4. At least that is what happened to me, but my starting phosphates was 0.05ppm. During the first week running the AF4 I retained phosphates around five times :)
I wasn’t rinsing for about a month and my phosphates got as high as .4. Granted I was also adding oysterfeast into the mix and that probably didn’t help.
 

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