Auto frozen food feeder

[salty joe]

That is a very cool feeder!

What kind of motor is the stirring motor?
How big is the propeller?
Is there any cleaning other than rinsing the food jar, does the feed line ever foul?

 

[Rick Mathew]

Very nice!!

I have been using a similar design for several months...here is a link to the post.

https://www.reef2reef.com/threads/diy-frozen-food-feeder.279232/#post-3386631

I have since made some minor modifications to the setup to make it easier to maintain, more reliable and able to keep the mean kinetic temperature at 30F so as to keep the food from going bad too quickly...I also added a temperature probe in the food container to monitor the temperature of the food slurry...

 

[bif24701]

It isn’t likely this would keep the frozen food cool enough to stop it from going bad. I’ve looked into these smaller fridges, but most only cool to around 55 degrees.

Needs to reach ~35 degrees.

 

[7hogwarts]

A friend of mine built something similar to this, but had one more component. He built in a RODI line to flush the food line afterwards to help eliminate any food leftover in the line. Works beautifully. Hopefully he will chime in here.

 

[Rick Mathew]

A friend of mine built something similar to this, but had one more component. He built in a RODI line to flush the food line afterwards to help eliminate any food leftover in the line. Works beautifully. Hopefully he will chime in here.

That is very helpful to keep the line from becoming contaminated with rancid food...I actually flush the lines by running the DOS backwards pulling water from the tank to flush out the food in the line...works well

 

[Rick Mathew]

Needs to reach ~35 degrees.

The frig I use can keep the food at 30F mean kinetic temperature no problem...

It isn’t likely this would keep the frozen food cool enough to stop it from going bad. I’ve looked into these smaller fridges, but most only cool to around 55 degrees.

The frig I use can keep the food at 30F mean kinetic temperature no problem...It is cooled with a compressor and not thermoelectric....

 

[Rick Mathew]

It isn’t likely this would keep the frozen food cool enough to stop it from going bad. I’ve looked into these smaller fridges, but most only cool to around 55 degrees.

Here is the data recorder results of the temperature of the food slurry...I have a LogTag temperature probe in the food slurry that monitors the temp 24-7

 

[Shaun Sweeney]

great diy stuff. quite right about drilling the sides of the fridge. I trashed a new fridge that way. Go out the back.

 

[ReeferAl]

One of my prior prototypes incorporated an RO flush of the line. My current version keeps all the tubing inside the fridge where it stays cool. The flow loop from/to the sump enters the back of the fridge where it meets the pump output and then re-exits the back. No food sits in the line outside the fridge.

 

[BluewaterLa]

This is really neat and well thought out.
I see some plans to do something like this in the future on a larger scale to fit my needs.
Thank you for sharing

 

[KJAG]

How long is the chilled/ refrigerated food viable for? Sitting here with a beer thinking of auto feeders now. Couldn’t build one nearly as squared away as anyone here, but hopefully soon one of you will invent something radical like a vending machine style, stockable system where you just load up a bunch of frozen cubes, then have a mechanical hopper/ arm that drops them onto a conveyor belt or something which exits out the fridge and into an awaiting doser. I work 24 hour shifts and would be nice not to have to rely on my wife to feed the tank. Not to mention a frozen compatible unit would be epic for vacations.

 

[Evan Kamien]

I've tried that but so far haven't gotten the bugs out so I shelved the idea. Figured I'd stick with my tried and true method.
A while back I bought an auger assembly taken out of a commercial ice dispenser. What I would really like to do with it is have it turning very slowly but continuously all day. I can't find any motor capable of doing that though. They're either too fast or have insufficient torque. Some day I'll give it another go with the new auger assembly. I'd like to have it drop cubes or chopped food directly into the sump
One problem I've found with small fridges or freezers is that they use the outer metal shell itself as the outside heat ex-changer. That makes it very hard to make any holes in the sides or top because you never know where the refrigerant tubing will be running. The back seems to be safe though.

Allen

Hey! hope all is well. What about a wiper motor from a car for the auger? TONS of torque and spins slowly with the gearing already. you could step down the voltage and get it to turn reallllly slow.

 

[ReeferAl]

Hey! hope all is well. What about a wiper motor from a car for the auger? TONS of torque and spins slowly with the gearing already. you could step down the voltage and get it to turn reallllly slow.

Thanks. I'll look into that the next time I have the initiative to work on this. If you turn the voltage down too low I believe it also decreases the torque though. I have a gear box from a commercial ice dispenser that I bought on eBay (the gears only- not the whole machine). It decreases the speed from the motor with a chain and sprocket and is built like a tank. I plan to eventually incorporate that into my design.

Allen

 

[zalick]

As far as food going bad, I haven't seen any problems with food up to a week old, but then fish also make it a habit of eating things like the poop of other fish so I don't think they're as particular as humans.

Allen

Allen - Great looking setup! Thanks for posting. I'd love to build one like it but my issue is the closest I can get a mini fridge to my tank is about 30 feet away. Have you ever heard of issues feeding food sitting in the fridge for a week or two? When I go out of town, I leave all the food thawed for the week in the fridge to make it simple for the person feeding. I've done two weeks many times and no issues. Currently I just do one week and have the second week pre-thawed in tank water then refrozen so they just pull it out after week 1.

Would you see any issues having food in 20-30' of line under the house at about 60 degrees for 24 hours? That would be the longest any food would stay in. Otherwise I could reverse the pump like you do until the line is clear of food.

 

[ReeferAl]

I can only give you my subjective opinions. In the past I tried stretching the feedings over 2 weeks but the mixture was smelling pretty funky by late in the 2nd week so I quit pushing it.
Personally, I would not leave food stagnant in 20-30' tubing for long. Not only would it be warm but it would have little oxygen so it would undergo anaerobic decay after a few hours.

Allen