Re-freezing frozen food?

[JohnK]

How much nutritional value is likely to be lost by breifly thawing frozen food, then refreezing it? Any other risks or problems with re-freezing?


I'm asking because I had the idea of making a simple fish goo (mostly mysis), setting it in ice cube trays, then adding a bit of sand to each cube. The idea would be to create SINKING ice cubes that would serve as one a day fish MRE's.

So, do people think this would hurt the quality of the food a lot?

Any other input or thoughts about this idea?

I did make a test batch and it seems to work well as long as the sand to water ratio is high enough. The ice melts fast so it's like a little mysis depth charge. I really like the idea of being able to just pop an ice cube in to do a day's feeding.

 

[ReeferMedic]

Every time someone makes fish goo, they are refreezing. I wouldn't worry about it. If it was out too long and spoiled, then I'd toss it.

 

[JohnK]

Every time someone makes fish goo, they are refreezing. I wouldn't worry about it. If it was out too long and spoiled, then I'd toss it.

Yea, that's pretty much what I was thinking. Thaw the food, rinse in a bit of RO, and drop into little ice cubes. Quick and easy.

 

[Liam]

i would be very careful of salmonella(sp) j/k

sounds fine too me as long as the food is kept cool and only breifly thawed.
You may find you can't add enough sand though to get them to sink,let us know how it works out.
i always try to thaw my food in saltwater though,its probably anal but i am not 100% happy feeding a fish or coral something that could have absorbed a good amount of fresh water.

 

[JohnK]

I've got "semi boyant" so far

 

[ReeferMedic]

i always try to thaw my food in saltwater though,its probably anal but i am not 100% happy feeding a fish or coral something that could have absorbed a good amount of fresh water.

I always thaw their food with tank water as well.

 

[alpha0r]

I buy a frozen "seafood mix" at the grocery store then thaw it out and grind it up and refreeze it. I haven't seen any problems yet. My fish and coral go for it and they all seem quite healthy.

 

[Leroy]

I feed with Jays fish food which is loaded with all kinds of good stuff for the corals and fish. I take it out of the freezer and let it thaw some making it easier to break off pieces and feed both my tanks.

 

[Greg Hiller]

Pretty slick idea, John. If you made several small cubes and dumped them in different spots in a tank it might be difficult for the greedy fish to get everything. Of course any bottom dwelling corals might not be too happy!

Not sure how big an ice cube is, but if it were 20 ml initial freshwater, it'd swell to 21.8 on freezing, displacing 21.8 ml tank water, and if your tank were on the high edge of salinity (1.029 g/ml) then 22.45 grams of tank water. So, you'd need ballast for your 20 ml cube of at least 2.45 grams/cube. Wet aragonite sand is about 3.29 g/cc, so I'd think 1 ml of wet sand would be enough per 20 ml cube. I've neglected a bunch of stuff, but it gives you a ballpark figure.

 

[JohnK]

So far I've been working with little ice cubes and a good pinch of sand. Freeze a thin layer of water on the bottom of the ice cube tray, then add sand and food, freeze, then add a tiny bit more water and freeze one last time.

I'll keep experimenting but one thing that I learned right away is that the ice melts so quickly that even if the cube wants to float, it doesn't do so for long.

 

[JohnK]

OK, this works great. I made another batch with less water/smaller cubes, but about the same amount of mysis, and a very little bit of CC. They sink easily and dissolve quite quickly.

This is so easy and such a time saver, try it

 

[Aquaman_68]

i would be very careful of salmonella(sp) j/k

sounds fine too me as long as the food is kept cool and only breifly thawed.
You may find you can't add enough sand though to get them to sink,let us know how it works out.
i always try to thaw my food in saltwater though,its probably anal but i am not 100% happy feeding a fish or coral something that could have absorbed a good amount of fresh water.

I don't think that is anal at all...I've been soaking my frozen cubes in SW for more than 15 years.

 

[TheBigDrewsky]

Pretty slick idea, John. If you made several small cubes and dumped them in different spots in a tank it might be difficult for the greedy fish to get everything. Of course any bottom dwelling corals might not be too happy!

Not sure how big an ice cube is, but if it were 20 ml initial freshwater, it'd swell to 21.8 on freezing, displacing 21.8 ml tank water, and if your tank were on the high edge of salinity (1.029 g/ml) then 22.45 grams of tank water. So, you'd need ballast for your 20 ml cube of at least 2.45 grams/cube. Wet aragonite sand is about 3.29 g/cc, so I'd think 1 ml of wet sand would be enough per 20 ml cube. I've neglected a bunch of stuff, but it gives you a ballpark figure.

Okay, now this scares me....lol

 

[JohnK]

Okay, now this scares me....lol

I think that translates into 1 good pinch of sand per cube

 

[stingythingy45]

Just tonight I thawed some formula 2 by accident without SW as usual.I'm very happy with the way it stayed together longer.Floated for about 1/2 then sank to the bottom.I wont be thawing it in SW,or even fresh anymore......just thawed dry works great.The jelliton or whatever seems to hold up better.

 

[Reefried]

I really dont understand this..doesn't the cube with sand melt within 2-3mins? if so then how is it a days worth of food or any different than just throwing the mysis cube right in?....do you turn the flow off? if I added a weighted down cube into my tank with the flow on its highly unlikely that it would stay on the bottom..not bashing just currious

 

[JohnK]

The reasons I'm doing it are as follows;
-I want the food rinsed, I don't like to throw unrinsed food in the tank.
-I don't turn the flow off, I need something that won't float and get sucked into the overflows before the fish get to it.
-I'm lazy as heck so I wanted something I could just pop in the tank without any fuss

For the above reasons, it works great.
I's not all that much food, but it's a quick meal that the fish get. Much better than my not getting around to feeding the fish at all. I don't feed a lot normally anyway, and the fish find plenty of stuff to pick at naturally occuring in the tank.

The cubes probably melt in 1-2 min at the most. The advantage is that they sink, then melt. This leaves the food to scatter at the bottom of the tank, insted of the surface where a lot of it will go into the overflows.