Guide · Automatic feeders
Automatic feeder not dispensing or clumping
Most feeder failures come down to moisture, batteries or the wrong food. The fixes EHEIM, JUWEL and Fish Mate give in their manuals, symptom by symptom.
Short answer
Check three things in this order: moisture, batteries and food. Damp air from the tank clumps food and jams the outlet, so keep the feeder out of spray and humid air or feed it dry air from a pump. Weak or rechargeable batteries can stop some feeders after a few days. Live, frozen or compressed food does not belong in a feeder.
Find your symptom
| Symptom | Likely cause | Fix |
|---|---|---|
| Food clumped or stuck to the walls | Condensation or spray reaching the food | Move the air stone away, reduce airflow, raise the feeder, add an air supply |
| Nothing drops at feeding time | Clumped food, packed food, or a dead battery | Empty, dry and refill loosely; replace batteries |
| Feeds for a while, then stops | Low battery, or rechargeables below the operating voltage | Fresh alkaline cells of the type the manual names |
| Display shows "LO" (EHEIM) | Batteries running down | Replace them now; the unit shuts off after about three days |
| Settings lost | Batteries out too long | Reprogram, and swap batteries quickly next time |
| Fish get only part of a meal (Fish Mate F14) | Meals dispense over about two hours | Judge the meal after the two-hour window |
Moisture: the main cause of clumping
Tank water evaporates, and a feeder sits right above it.
- Fish Mate F14. Fish Mate says condensation inside the F14 can cause food clogging or failure to dispense, and that air-pump spray near the feeding hole can contribute. Its remedies: try pellet food, move the air stone away, reduce airflow, raise the feeder 25-50 mm, or connect an air pump to the feeder's AIR connector.[1]
- EHEIM autofeeder. EHEIM says the drive unit and air-intake opening must not sit in the humid air of an open aquarium, the air intake must not be covered, and the unit must never be immersed.[2]
- JUWEL EasyFeed. JUWEL says the EasyFeed can be connected to an air pump to help keep the food dry.[3]
Fish Mate and JUWEL both offer the same remedy: an air port fed by an air pump. Use it if your feeder has one and your tank is humid.
Mounting: where the feeder sits
The F14 manual says the feeder sits over a feeding hole in the hood (cut a 30 mm, 1-1/4 in hole if there is none), or on two supplied clamps on tanks without a hood.[1]
Closer Pets' product page lists a condensation tray as one mounting option, but the F14 manual says condensation-tray mounting is not normally recommended unless an air pump is connected to the AIR port.[4][1] Follow the manual. The F14 manual also says the feeder is not designed for outdoor ponds.[1]
Batteries
- Use the type the manual names. The EHEIM autofeeder runs on two AA (LR6) 1.5 V alkaline batteries, and EHEIM says it must not be operated with rechargeables.[2] Rechargeable AA cells run at a lower voltage, which is why a feeder can start fine and stop a few days later.
- Act on the warning. When the EHEIM shows "LO", it keeps feeding, but after about three days the display blinks and the unit shuts off.[2]
- Swap quickly. EHEIM's settings are lost if the batteries are not replaced within about one minute.[2] JUWEL's EasyFeed must be reprogrammed whenever its batteries are removed.[3]
Food
- Dry food only. EHEIM says its autofeeder is for dry food such as flakes and granulates and must not be used for live or frozen food.[2]
- Do not pack it down. JUWEL says food should not be compressed in the container.[3]
- Try a different form. If flakes keep clumping, Fish Mate suggests pellet food for the F14.[1]
After any fix, test again
Once it is dispensing, run the feeder for a full trial before you rely on it. The feeder test guide shows how. A feeder that has jammed once can jam again, and we found no independent failure-rate data for any model.
Next
Questions
Why is the food in my automatic feeder clumping?
Moisture from the tank is the usual cause. Fish Mate says condensation inside the F14 can clog food, and that spray from an air stone near the feeding hole can add to it. Move the air stone away, reduce airflow or raise the feeder.[1]
My EHEIM feeder shows LO. Will it still feed?
For a while. EHEIM says it keeps feeding after LO appears, but after about three days the display blinks and the unit shuts off. Replace the batteries within about a minute, or the settings are lost.[2]
Can I use rechargeable batteries in my fish feeder?
Not in the EHEIM battery autofeeder: EHEIM says it must run on two AA alkaline cells, not rechargeables. Check your own manual; other models may differ.[2]
Can I put my Fish Mate F14 on the condensation tray?
The F14 manual says condensation-tray mounting is not normally recommended unless an air pump is connected to the feeder's AIR port. Use a feeding hole in the hood or the supplied clamps instead.[1]
Can I use frozen or live food in an automatic feeder?
Not in the EHEIM autofeeder, which EHEIM says is for dry food such as flakes and granulates only. Wet food spoils and clogs, so treat dry food as the rule unless your manual says otherwise.[2]