Art by Alexander Vasiljev, Copyright © 2015


Wednesday, November 26, 2014


Feeding schedule and portion size are important parts of ranchu grooming. Both depend on the season of the year and the age of ranchu along with the goals of the keeper.

Ranchu are coldblooded animals and their metabolism is directly correlated with the water temperature. It is important to observe seasonal temperature fluctuations and adjust ranchu feeding accordingly. Below is a table showing different temperatures and their effect on ranchu:

32-43 F (0-6°C) - hibernation state
44-54 F (7-12°C) - semi-hibernation state
55-64 F (13-18°C) - intermediate state between hibernation and active states
65-75 F (19-24°C) - ranchu are ready to spawn
76-86 F (25-30°C) - ranchu grow actively 
87-97 F (31-36°C) - ranchu growth slows down
98-100 F (37-38°C) - upper temperature limit for ranchu

It is beneficial for ranchu to hibernate. However, in my case, bound by the indoor set up, the water temperature doesn't drop below 55-64 F (13-18°C) keeping my ranchu in the intermediate state, between hibernation and active states. Their digestive tract works noticeably much slower as their activities calm down. At this time, I feed them only once or twice a day, depending on the temperature. In the spring the temperature rises and when "the stars align" the ranchu will spawn. I increase the amount of feed from two to three times per day. In the summer months keeping ranchu indoors has its advantage. With my temperature controlled environment, I don't have to worry about high temperatures above 86 F (30°C). The feeding is three to four times a day.

I feed as much as my ranchu can collectively eat in five minutes. Although, regardless of the method by which the amount of food is determined, observing ranchu and adjusting the food amount according to their appearance is a must. Overfeeding is not good for ranchu, as for anybody else, it shortens their life span and may prevent them from breeding.

I use the above schedule for my nisai and will continue using it when they turn oya age. On the other hand, it is very different with the fry, BBR, CBR and tosai. In upcoming months, I will share my feeding schedule for the young fish, but for now I will say that correct feeding regime is crucial in the first year of ranchu development.

For its very convenient and consistent way, I have been using automatic feeders to feed my ranchu with high quality dry pellets. It is especially helpful when I have to feed three or four times a day and my timetable doesn't allow me to be around. Ranchu appreciate the schedule and quickly learn at what time the food is given and gather around the feeding area. Afterwards, they can "plan" their time, whether to forage for algae, promenade back and forth in the tank or nap. I find that automatic feeders are actually helpful in preventing overfeeding. The many temptations I have had to give an extra pinch or two of pellets to my ever hungry ranchu are now prevented by the feeder.

Among the several automatic feeders available, I have chosen Eheim Everyday Fish Feeder. It is reasonably priced for what it can do, programable for up to four meals a day, has sizable food reservoir and long battery life. One unfavorable feature of this feeder is that it doesn't dispense exact amounts of pellets each time. As the pellet reservoir empties, the portions may become irregular. This is, however, not a big concern of mine. I learned to keep the reservoir full and don't let it get completely empty. It works best with pellets larger than 1.5 mm in size.

For smaller pellet size and granules to feed the fry, I found that Fish Mate F14 Aquarium Fish Feeder is the best. It has 14 compartments and can dispense food for up to four times a day. I use this feeder to supplementally feed the fry with granules size of 360-650 microns. I especially like that it slowly dispenses food for over a period of time, giving every fish a chance to eat. An air tube can be attached to the feeder to keep the food from clumping. One thing about this feeder is that you have to refill it quite often, but its overall convenience beats that.

Eheim Everyday Fish Feeder
Fish Mate F14 Aquarium Fish Feeder