P21 Automatic Pond Fish Feeder – 21 Day Quartz Timer Feeder for Ponds & Large Aquariums, Waterproof Battery Operated, Adjustable Portions, Suitable for Pellets & Flakes

This automatic feeder works great for vacations or just daily feeding. I know some reviews have mentioned moisture building up. Because I read those reviews we do not use the cover and we have had no problem with moisture. I would imagine moisture buildup in the feeder is also a function of how warm your water is in your fish tank. We do not heat our tank water so maybe that is another reason we do not have a moisture problem. If I had to critique it, I wish there were more than 14 individual feedings, I would definitely purchase one that fed a little bit more than 14 times. Setting the feeder up was fairly intuitive. We went on a vacation that was over a month long and the battery had no problem (we did have to have a neighbor come and replenished the food though).

Any review of this product needs to start with how it works which may not be readily apparent from the photos and description. The feeder is composed of a plastic ring divided into 14 equally sized compartments; the sections partition the food into the 14 different feedings. The timer in the middle moves one revolution in 24 hours and has spots to place 4 pegs; as these pegs near the top (12 o'clock) position, they engage with inside of the ring and over the course of about 2 hours push the ring around 1/14th of a revolution. This in turn pushes the compartment at 6 o clock over the opening and any food will fall into the water below. This is a rather simple mechanism but leads to some quirks that are the focus of this review.The first issue with this design is that the ring simply lays inside the feeder and isn't held very tightly. which means that the ring can rotate out of position easily. The design also means that if there is any food under the ring, it can lift it up and it will "miss" food; this practically means that you must put it down empty and then fill the compartments; if you need to pick the ring up for any reason you basically have to start over filling it. The documentation also states that it feeds over the course of two hours; while it might take two hours for the compartment to fully move over the hole, in practice the food gets piled up against the left wall of the compartment as it is pushed around in its path and ends up basically getting mostly dumped in at the end of the two hours. I am using Hikari micro pellets and loach wafers, and I would say if I have it set to feed at 6, most of the food will get dropped into the tank between about 7:30 and 8. It will also get pushed in, I haven't experienced where the food doesn't get dropped in, it just isn't as spread out in time as the paperwork would make it seem. Also, if you don't line the compartments up perfectly with the whole, you may get where it doesn't drop all of the food at say your 6am feeding; it will however push the remaining food in at the next set time.The other issue I have is that the times you can select are fairly inflexible; IIRC there are 6 possible feeding times; if you don't like then those are you can simply set the time on the feeder to compensate (for instance, if you don't want it to start at 6 but instead 7, set the time on the device an hour ahead). However, you cannot make the feedings closer together or spread out than what it is designed for. This isn't a huge huge issue but I would have liked more time options or one where I could set it any time I wanted.All of this being said, the feeder hasn't had problems with moisture which was my biggest fear; the pellets have stayed dry and I am not using the air tube option that the feeder has. It is fairly easy to load and to take on and off its mounting brackets, and when empty I can wipe it down to clean it. I also like that I can change what I am feeding the fish from day to day unlike other feeders; some days I include algae wafers for the snails and in others I put in some other foods that I don't give but a few times a week. I appreciate that I can load it on Sundays when I do water changes and don't have to worry about it; I do check it periodically just because that is how I am, but I really haven't needed to mess with it. I haven't had it long enough to check the battery life claim but I see no reason that it wouldn't last a long time; it is basically a wall clock mechanism and those seem to last a while.Overall I would recommend this feeder over the kind that rotate and dispense all the food; while it is a little fussy, I think that the more analog way this works is more reliable and I like the flexibility in food I can use. Overall it has been a good device and I'm glad we have it.

It's closer to 4.5 stars. I've used the drum autofeeders in the past and hated them because it's so hard to guess the opening for the right amount of food to dispense, and the moisture makes short, moldy work of flake food. I have 4 tanks, I bought one to try out: it was a bit frustrating at first because the tray moves/lifts off so easily that it took me 3 (irritating) tries to get the food in and the feeder situated on the aquarium. I learned it's very helpful to stick a fat pen (sharpie, etc) into the opening to keep it from spinning. The aquarium I tested it out on is 55 gal, and that has the LED light inserts - I just removed one of the lights, pulled back the plastic cover that protects the light, and set the feeder so that the opening was over the exposed water. It was too close to the water for the flake food, and I was not interested in hooking up an air pump, so I elevated it by putting some cut wood paneling pieces under it to raise it about 4". That helped tremendously, but sometimes the flakes still got too moist and wouldn't dispense because it stuck to the sidewalls of the tray. So rather than raise it anymore, I just opened the cover - viola! That did it. I have several different kinds of fish, so in addition to flakes, there are shrimp pellets, freeze-dried bloodworms, and algae tablets (broken into pieces. What makes this great is that it dispenses exactly the amounts of the different foods rather than random mixture from the drum-style feeders and this is what sold me. I have ordered 3 more for my other tanks - all of which I can make work in a very similar fashion. Do test it out before you go on vacation - make sure you've worked any of the bugs out and that you're confident it will work while you're gone. I was ready to get rid of my tanks because it was so stressful trying to arrange someone to come over to feed them while I was out of town, but now this has removed the stress and I'm glad that I can keep my fish tanks:)The cons are the irritation at how easily it is to mess up the food you so carefully distribute into each cell, just by a little bump (thus having to do it all over again), and the price - I don't see how in the world this thing should cost almost $25 - that's highway robbery for such a simple gadget (no LCD display or anything - just a simple clock mechanism and all plastic parts). But I'm obviously willing to pay it because it's a simple solution that works really well.*Update, I'll bump it up to 4.75 stars (still the price factor is ridiculous), but I did order the other 3 and have them all on my tanks. They work so well, I use them as everyday feeders (they were originally intended as vacation feeders only). Using them creates less wasted food because it dispenses a little at a time over an hour, so the fish have time to get it all rather than having some of it get sucked up in the filter. I have it feed them 2x a day - so once a week I fill all the feeders (it's helpful to remove the feeder, set it on a table, stick a fat pen (or something comparable) into the opening to stop the wheel from spinning, and use a small funnel when adding food to the chambers.)