DIY (Auto) FROZEN FOOD FEEDER

[t5Nitro]

If it stays fresh at his fridge temps, why would you need to keep it colder?

 

[LondonReefer]

If it stays fresh at his fridge temps, why would you need to keep it colder?

Yep it's a fair point

At lower temp and higher salinity it would stay fresh indefinitely I think though. Was just a thought

 

[robbyg]

If it stays fresh at his fridge temps, why would you need to keep it colder?

If you put raw shrimp etc in your fridge for a week it would most likely start to smell pretty bad! You really need it to be frozen to guarantee freshness.
On the subject of temperature, there is no way your going to get to Zero much less -5C. A full size fridge typically runs at +4C and it’s pretty hard for a peltier based chiller to match that much less exceed it unless you keep the cooling area very small.

 

[LondonReefer]

If you put raw shrimp etc in your fridge for a week it would most likely start to smell pretty bad! You really need it to be frozen to guarantee freshness.
On the subject of temperature, there is no way your going to get to Zero much less -5C. A full size fridge typically runs at +4C and it’s pretty hard for a peltier based chiller to match that much less exceed it unless you keep the cooling area very small.

Don't want to hijack this great thread, but you could in a small freezer though? High salinity liquids would stay liquid in the freezer

 

[YankeeTankee]

Nice write up! I'm building a frozen feeder as well and have been going back and forth on whether to have 3 containers for food, water, dispensing mix like the ops OR just run a small pipe on a low flow closed loop through the fridge (disadvantage cools aquarium obviously) but removes need for flushing line, one container doses food into that line.

 

[WallyB]

Looks like a great design and clearly works well for you. I think what you've made is optimal but curious to know if you thought about storing the frozen food in much higher salinity water such that it wouldn't freeze? We'd have to look up the freezing point at varying salinity levels but normal seawater freezes at around -2c so I can believe you could get it to say -5c and still liquid if you had a higher salinity. Could pump that from a mini freezer straight into the tank? And then have your clever way of cleaning the pipes out too

Yep it's a fair point

At lower temp and higher salinity it would stay fresh indefinitely I think though. Was just a thought

@LondonReefer,

That is a very interesting thought. Really clever thinking.
Basically you are saying "run the Frozen Feeder on Antifreeze and Feed the Fish Salty Chips" LOL

But Jokes aside it is interesting, and I actually thought about using Salt Water. At least for the Concentrate water. For a different reason than bringing down temp.
I was thinking it's like pickling the Food, or a preservative to keep it fresher longer.
I was also thinking will the Frozen Bits of food Sink More since Salt Water is more dense.

Never thought about temp, so great point. Something to consider.
I don't think the Koolatron will run below Freezing. It get's close.

Thanks for the thought. Something to Experiment with.

 

[WallyB]

Don't want to hijack this great thread, but you could in a small freezer though? High salinity liquids would stay liquid in the freezer

I actually was thinking of using a mini fridge in basement. But didn't want to Drill it, when I read the Label on today's Non-Freon Gases. Explosive. Other Fridge is too far and my Tank Area has no space.

You certainly have ideas.
I'd love to see you build a Frozen Feeder, and what it comes out like.

 

[WallyB]

If you put raw shrimp etc in your fridge for a week it would most likely start to smell pretty bad! You really need it to be frozen to guarantee freshness.
On the subject of temperature, there is no way your going to get to Zero much less -5C. A full size fridge typically runs at +4C and it’s pretty hard for a peltier based chiller to match that much less exceed it unless you keep the cooling area very small.

Exactly Why I fill the unused space in the Cooler with Syrofoam.
Also the Reason the Food Concentrate Bottle is next to the Coolers Cooling Radiator Fins.

I think the Frozen stored in Salt Water, and Cooler running at 1 C would keep Food Fresh for a Week.
A week before refills is my Goal.

Actually I've been thinking. 5 Days will be my Setup.
Just so the Fish still like me. I can tell they already love the feeding spots. You see it in the video.
They are beginning to ignore me. Not as much "Wally's Here Excitement"

Monday to Friday is Auto Feeder.
Sat is some Simple Maintenance Cleaning (The Concentrate Bottle only, since the rest of the system cleans itself)
Sun is Refill night.

 

[LondonReefer]

Think it's a great idea to feed them yourself on the weekend, not least because you'll be forced to see who eats and who doesn't etc. Obviously hopefully everyone always eats, but more automation means less checking. I have a heavily planted freshwater tank that just gets pellets on an auto feeder, honestly you can forget about it for a month... Pros and cons to that lol

Yep an anti freeze for sure. I think your salt preservation would work too tbh. One day I'll dig my old microscope out and run a test for us all

Just an FYI for the fridge, I think (but don't take my word for it) the door shouldn't have anything going through it - so that could be drilled

 

[WallyB]

Just an FYI for the fridge, I think (but don't take my word for it) the door shouldn't have anything going through it - so that could be drilled

Yes, the Mini-Fridge Door and probably the sides are safe for drilling. Most fridges have thier cooling system at the back.
Close inspection will reveal the safest way.
My Mini Fridge isn't one with a Freezer Compartment and the Cooltatron runs colder than it by a couple of degrees.

 

[WallyB]

Article out Barely a Day ( Thanks for Feedback and Idea's ) ** First Upgrade **

So thanks all the Folks everyone for their comments, and thoughts.

You participation helped me make article improvements, clarifications and .....
It all got me thinking about some additional improvements. (Simple Stuff)


Upgrade #1: ( New Bigger Concentrate Bottle )

- As seen the Photo, the Vitamin Bottle is much bigger than the Ice Tea Bottle (Bigger Base CAP too)
- The Extra Volume provides not only more storage for Food, but allow for more Thermal Mass with Water and Ice
- Plus with the Wider Cap Base, the Mag Spinner has more room. Means I can get the Extract Tube right to the bottom, so the Food is being picked up better.

Upgrade #2: (COOLANT : Salt Water / Ice Cubes ) This upgrade was inspired by @LondonReefer

- Going to try some Higher Salinity Water (1.045). See what temp my Box Feezer will get the water
- Also making some mini (RO Water) cubes of ice to drop into the Larger Concentrate bottle
- NOTE: I am aware that too much Salt Water can increase my Tank Salinity (It won't be much across 300Gals in 4 tanks)
- So I still will be using Fresh Water for the Rinse Bottle
- And I'll calculate any offsets, Monitor and deal with the Salinity Stability with my DIY Auto Water Changer/Auto Top Off.

• The First Upgrade is tested and works way better.
• The 2nd Upgrade is Cooling in Freeze and I'll test Temps once installed.

Thanks Everyone.

 

[WallyB]

Results are in for Salt Water Coolant.

Now the Original Water comparison is a bit off, since I used RO Water and didn't wait a day. It was previously running at around 2.5 Degrees C.

So at this starting point with New Chilled (Salt Water+Some FreshWaterConcentrate), is a Lower 4 Degree C improvement.

Temp may rise over time, but every bit of Early Cooling on the Food is longer Freshness.

 

[WallyB]

So with the Salt Water in the Concentrate Container, adjustments had to be made.

When I ran the original programming ALMOST NO food came out!!
The Salt Water is denser so it floated better, like swimming in the Ocean vs a Fresh Water Lake.
At first I thought it would never Sink, but it did.
In General the Food is more Boyant.

It was a easy fix. I stirred briefly and Let the Food Settle Longer, before extracting with the Bottom Placed tube.

 

[WallyB]

LAST CHALLENGE after Ajustments......(Food Portion Calibration)

I still have one thing Left to Fine Tune which is getting a Handle on the Feeding Portions.

Normally (before Auto Feeding) I would feed by just breaking off a piece of Frozen, and that would be a daily portion split between the Tanks.
That piece was rinsed thru a brine shrimp net, and put into a small cup of water.
Then Using a syringe I would feed each tank certain amount based on a visual.

Now with an Auto Feeder, I'm putting in 5 Chunks for 5 Days about the same size chunk I would do in each day.

It's a bit tricky guessing how much actual food gets sent to each tank, and tuning the Portion Extracts.

So my way right now is just a few Manual Dosing Runs doing same visual checks and then programming each Tank dose as one Auto Feed portion (Different for each tank)

I'll will then simply watch each day to see when the food runs out.

It may take a few iteration to get things Perfectly Calibrated.

 

[LondonReefer]

Wow, you've tested all of those ideas really quickly! Glad you've had some improvements to the already great design

Super interesting that higher makes the food float too. It makes perfect sense but I hadn't even considered that, I guess I thought it would just raise the salinity of the food (your pickled idea) and the relative density wouldn't have changed much. Thinking about it now, I guess you would expect that to take a few hours at least

 

[robbyg]

Wow, you've tested all of those ideas really quickly! Glad you've had some improvements to the already great design

Super interesting that higher makes the food float too. It makes perfect sense but I hadn't even considered that, I guess I thought it would just raise the salinity of the food (your pickled idea) and the relative density wouldn't have changed much. Thinking about it now, I guess you would expect that to take a few hours at least

That brings up an interesting question. How safe is it to feed fish food that has a high salt content?
The fish we catch and eat have very little salt in their flesh and so does the natural food that fish eat.
At first this all sounds crazy but if you think about it fish biology is designed to remove salt from their bodies using their Gills and Kidneys so that they can hydrate themselves with fresh or semi fresh water. Over the long term can their organs handle the extra salt from pickled food?

 

[WallyB]

That brings up an interesting question. How safe is it to feed fish food that has a high salt content?
The fish we catch and eat have very little salt in their flesh and so does the natural food that fish eat.
At first this all sounds crazy but if you think about it fish biology is designed to remove salt from their bodies using their Gills and Kidneys so that they can hydrate themselves with fresh or semi fresh water. Over the long term can their organs handle the extra salt from pickled food?

Hmmm.
Good Point.
I with thinking about that when I made the Salty Chips joke Ealier, then I forgot.

A few seconds or a minute soak in higher Salt Water wouldn't be an issue.
Keeping the Food in 1.040 all week long would make it super salty (if the frozen soaks in the Salt).
I do add the ice cubes so Salinity does drop as the Cubes melt (and they melted in less than an hour)

I think I'm fine if the Final Frozen Soup ends up 1.026 (I stir often)

But @robbyg GOOD POINT your brought up (so I don't just go with Higher Salt Water only)

 

[LondonReefer]

That brings up an interesting question. How safe is it to feed fish food that has a high salt content?
The fish we catch and eat have very little salt in their flesh and so does the natural food that fish eat.
At first this all sounds crazy but if you think about it fish biology is designed to remove salt from their bodies using their Gills and Kidneys so that they can hydrate themselves with fresh or semi fresh water. Over the long term can their organs handle the extra salt from pickled food?

I've just been thinking the same thing and was about to reply with a similar point, how funny

I think firstly, at 1.045 you'd think this would be fine for a while.

At higher concs of salt and/or much longer times that raises the question of how well they (fish, seahorses, rest of the critters) can expel salt as you say.

Surely someone on this forum has a better handle on the biology of this than us? In the meantime - I'll drop some mates who did their undergraduates in natural sciences... Would be good to get answer

 

[WallyB]

I've just been thinking the same thing and was about to reply with a similar point, how funny

I think firstly, at 1.045 you'd think this would be fine for a while.

At higher concs of salt and/or much longer times that raises the question of how well they (fish, seahorses, rest of the critters) can expel salt as you say.

Surely someone on this forum has a better handle on the biology of this than us? In the meantime - I'll drop some mates who did their undergraduates in natural sciences... Would be good to get answer

I think we have a 3 Way Agree here. Too Salty food might not be a good idea!!

It's still a good idea to Super Cool the Concentrate Water but add Fresh Water Ice cubes to dilute back to Normal Sea Water (With the RO Water Ice cubes).

 

[WallyB]

HERE IS FOOD FOR THOUGHT...... LOL

How about the Other Way around. Keeping Food in RO water. Is it ok that they eat Low Salt Food? Probably.

Can I use Sea Water Level 1.026 Salt Water for the Food Storage? (Fish eat pieces of fish in the ocean floating around)

What is best?

Go back to RO WATER? Sea Water ? if not High Salt Water.

I don't want to harm all my fish......

For now I'm going back to RO water. Add the Mini RO Water ICE cubes.