Tank setup
Fry and grow-out tanks: what feeding sources do and do not say
What Merck says about feeding growing fish, why no source supports leaving fry to an automatic feeder, and what to check daily instead.
Also listed as grow-out tank, fry tank, breeding tank
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Short answer
No source we read supports automating fry feeding while you are away. Merck gives general rates of 3-5% of body weight per day for growth diets but says rates vary with species, age, system and temperature, and that needs are known for only a handful of species. Plan for a person to check the tank daily.
Key facts
- Feeder mounting
- Not confirmedNo feeder maker addresses fry.
- Food form to check
- Not confirmedEHEIM, for example, says its feeder is for dry food and never live or frozen food.
- Aeration option
- Not confirmed
- Check valve and pump position
- Pump above the water line; if it must sit lower, fit a check valve near the rim[1][2]Aquarium Co-Op says a pump below the water level needs a check valve and suggests placing the valve near the top of the tank so water stops at the rim.
- Water-change tool
- Regular changes; Merck lists one every two weeks, amount by stocking level[3]General schedule, not fry-specific.
- Light timer
- Smart plug or mechanical timer for the light, within its stated load rating[4][5]TP-Link rates the Kasa EP25P4 at 15 A and 1/6 HP; Intermatic rates the TN311 at 15 A resistive and 1/3 HP. Keep plugs away from splashes.
Watch out for
- Growth rates are not a vacation rule. Merck's 3-5% of body weight per day for growth diets is a general rate that varies with species, age, system and temperature.
- We found one fasting study we could not read. A 2021 paper on fasting in larvae and juveniles of one ornamental species exists, but only its title was available, so we draw nothing from it.
What fits
Product details below are the seller's own description unless a source is shown. Pick the variant named for each item.
Liquid test kit
API Freshwater Master Test KitChoose the Freshwater Master Test Kit. On Amazon, check that 'Ships from / Sold by' names Amazon.com or the brand before you buy.
API says it measures pH, high range pH, ammonia, nitrite and nitrate, with seven test solutions.
See how long can fish go without food for what the sources do and do not say.