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Automatic Feeder

By Steven Pro

With summer upon us and vacation season in full swing, I felt it was a good time to review some of the automatic fish feeders and discuss some other options and tips I have for ensuring the proper care of the aquatic pets while one is away. Let's get  right to it!

Quick Tips:

This unit by Eheim is not rated, but is an example of a feeder with digital programming.  Photo Adam Cesnales

Before going away on vacation and entrusting the fish to the fate of these types of devices, I would strongly encourage the hobbyist to test the performance of the feeder beforehand. This will permit plenty of time to tweak the automatic feeder so that it gives the fish just the right amount of food -  not too much or too little.

About two weeks prior to leaving, try running the automatic feeder into a cup or some similar device so it is easy to monitor exactly how much food is being delivered at each feeding. This will also allow for time to make adjustments to the feeding dosage. After about a week of this kind of use, move the feeder over to the display and see how it functions there. There are several things to watch out for. Now that the feeder is actually feeding fish, does it appear that they are receiving enough food? Have they become accustomed to the feeder’s schedule and where the food is coming from? After months to years of being trained to come to the front of the tank when a person approaches the aquarium and lifts the hood, they now have to realize that food will be dispensed when no one is nearby at a set time. Also, check to make sure that the currents and filtration are not removing the food before the fish have a chance to eat.

The Human Fish Feeder/House Sitter:

If, instead of a mechanical feeder you have arranged for someone else to stop into the house to check on things and also feed the fish, I have a few words of warning and suggestions to keep the fish safe while the owners are out of town. First off, pre-measure all the food. Don’t give a novice fish keeper a big can of food and expect to come home to anything but a tank full of dead fish and a mass of rotting excess food at the bottom of the aquarium! I prefer to use the little containers that one can buy at the local drug store which are designed to hold daily doses of medication. . They have seven small, separate compartments and are marked for each day of the week. These are perfect for holding small amounts of dry fish food. If the fish also receive frozen food, purchase the frozen food that comes in little cubes (like small ice cube trays) and tell the house sitter exactly how many cubes of food per day. Alternatively, one could purchase a second pill container and placed portions of large slab frozen foods in each compartment.

Last, hide the rest of the fish food! Don’t leave cans sitting around the tank. Inevitably, the part-time novice fish feeder will feel that the fish are not getting enough to eat and will feel some sort of compulsion to give them more. Help them resist this urge by removing and hiding the food reserves and force them to stick with the rationed portions.

Automatic Feeders

Grasslin Rondomatic 400:

This unit has the nicest programming features of any automatic feeder that I have ever used. It also has individual compartments for each feeding so the aquarist can load each section with exactly the amount of food they want to have dumped. You can even alternate the foods so that the fish are fed a variety of dry foods instead of one standard offering. It also has another feature that I prefer. It is not battery operated. It plugs into a standard outlet.

For all those pluses though, it has some drawbacks. The little compartments that this system utilizes are a pain to clean. Each one has to be individually removed, cleaned, and dried thoroughly every so often before being returned to the base unit to keep moisture and mold problems to a minimum. Also, all those great positive features that I prefer cost money. This is the most expensive unit discussed in this article at about $70-80.

Nutrafin (Hagen) 2X:

This is one of the least expensive units I have ever used (about $15-20) and it is a good example of the old adage that you get what you pay for. It is battery operated, which allows the unit to be conveniently located just about anywhere. However, it is also prone to run out of juice and go unnoticed when used continuously. It also does not have the most sensitive adjustment when it comes to the amount of food it dispenses. If the intention is to only use it for a relatively short vacation once in awhile then it is an ok choice because of how inexpensive it is. You can easily just drop in a fresh set of batteries for each trip to ensure the power is there for the entire time, while hopefully dialing it in close enough that the fish neither starve nor are overwhelmed with excessive amounts of food. But, if you are looking for something to take over the daily task of dry food feeding of a staple diet there are better choices.

Nutrafin (Hagen) ProFeed:

The ProFeed is an improvement over its 2X sibling. It has a nice programming feature plus an override button to test how much food the unit is dispensing. This added feature makes it a real plus in my mind. The downside is that added feature about doubles the price of this unit to around $35-40 over the 2X but in my opinion it is well worth it.

Penn Plax Daily Double II:

The Penn Plax Daily Double is very much the same in basic design and function as the Nutrafin 2X unit with the same drawbacks. Both are battery-operated. Both have rather crude adjustments for how much food they dump. However, both are inexpensive at $15-20. Either is ok for use for a vacation, but I would not use either for regular daily duty.

Photo Adam Cesnales



Photo Adam Cesnales

The Rainbow/Lifegard unit is another one of the better options for an automatic feeder. It is powered by standard household current instead of a battery. It has individual compartments to hold predetermined portions of food. And, in contrast to the Grasslin Rondomatic 400 it is easy to clean and service. However, it’s programming features are not as convenient to the Grasslin unit.

The Downsides of Using Automatic Feeders:

There are several major drawbacks with using any of the automatic feeders. For one, fish tend to learn rather quickly where and when the timer is going to trigger and food is going to fall from the sky. Once they have learned this, a feeding frenzy usually ensues when the feeder drops it food. In many instances this causes a lot of splashing which can get the remaining food wet. This can lead to mold growing and the left over food going bad or clogging the feeder dump mechanism. Even the humidity in the immediate vicinity of an aquarium can cause this to happen, particularly when the aquarium uses a canopy which can trap in even more moisture when it is not properly vented or fan exhausted.

Possibly worse than not feeding your fish at all, "feeding blocks" have terrible potential for water pollution.  Photo Adam Cesnales

Also, fish food manufacturers go to great lengths to seal up their jars and cans to keep the food fresh. I always make it a point of making sure the lids are screwed back on tightly after each use. I even know of friends that keep their dry foods in the refrigerator to help keep the food fresh. This is a great idea if your significant other will tolerate it. I am not so lucky! Nevertheless, placing food in an automatic feeder where it is open and exposed to atmospheric air is not a great way of providing your aquatic pets with a highly nutritious diet.

And finally, even with fine-tuning, an automatic feeder is non-responsive. It can not adjust to the particular needs of your fish over time, or even on that particular day. That leads to either chronically under-or-over-feeding, neither or which is good for the fish or their environment. So, if you cannot find someone competent whom you can trust to feed your fish while you are away, use an automatic feeder while you are gone. But, I would not rely on one to take care of all your fishes dietary requirements day in and day out.

So, that's it for my impressions of automatic feeders! Have a great vacation!

Eheim auto feeder for pellets   3/15/07
Hi Bob,
Just curious if you somehow modified your Eheim feeder for use with those little Spectrum pellets.
<Nah... just fool with the ding dang slider on top... those pellets don't seem to be all that uniform... and as the hopper gets less full... less fall through whatever incremental setting I have it pushed/pulled to... A hint here... Do get/add a bit of that sticky Velcro tape to the bottom of the unit and the plastic tray it mounts in... to keep all horizontal>
  I received my feeder and in testing it out the smallest number of pellets I can get to dispense is in the ballpark of 400-500 pellets, or about 10x the usual "pinch" I feed the fish 2-3 times a day. This is when the little "door" is open about 1/8" or less...the next smaller adjustment basically closes it off.  Maybe mine's missing something in the adjustment of the bin?
<Mmm, yes... there is a greyish sliding bit that is fluted for finger manipulation...
It is a nice quality feeder if I can get it to work for me. If anybody is looking for these, has them on sale for $35....
<A bargain! I have two... and these have given good service for many years... I usually use rechargeable AA's... but not in these... BobF>

Eheim auto feeder for pellets   2/24/07
<Hello there>
I was going to order an Eheim 3581 auto feeder online, and understand Bob has experience with them.
<Yes... in fact I just pressed the "manual" override/feeding actuators less than fifteen minutes ago... while re-warming coffee!>
Everything I can find on this feeder only mentions that is handles flakes, but do you know if it works well with pellet food, like Spectrum?
<Yes, does... Is what I have in mine! There is an adjustable/sliding selector on top of the refillable food-hopper... for different size foods, amounts per feeding. The only bugaboo I have with these units is the bit of time, re-doing it takes to program them... and has to be re-done every time the ding dang AA batteries run down... But good units otherwise. BobF>

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