UMT MOOC: Ornamental Fish Culture - Topic 7: Seed Production - Degree of Care - Feeding and Observation

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One of the most fun activity for a fish hobbyist is feeding time. Occasionally, we may get carry away of over feeding which will lead to numerous problems. For examples, water quality degrade due to leftover food or fishes having indigestion issue due to bloating and may succumb to Dropsy. The general guideline is you need to feed to satiation or in the state of being full. However, how do we know the fish is full? Well, if the fish stop eating, then we stop feeding.. However, that is not a good measurement as some fishes will continue eating way beyond their capacity.

Therefore, there are several rule of thumbs that we can use to guestimate the required diet for fishes. For live feed, 5 till 10 individual / ml. Another measurement is calculate the percentage of body weight against the fish age. For fry or juvenile, 40% of body weight and for fingerling and young fish, 20% of body weight. When we have the estimation of how much food we should give for different life cycle of the fishes, the next question is how frequent we should feed the fish?

There are many thoughts on the frequency of feeding. The common feeding schedule for most fingering or adult fishes is twice per day (around 8-9 a.m. and 4-5 p.m.). Larvae, fry, and juvenile have different feeding schedule, some breeders feed three (6 a.m., 2 p.m., and 22 p.m.) or four (6 a.m., 12 p.m., 6 p.m., and 12 a.m.) times per day. Furthermore, different species have different diet and feeding behaviour. Moreover, feeding frequency for broodstocks is quite different as we need to feed the pair of fishes as frequent as possible and high protein and fat diet so these fishes are strong and healthy to breed and mate to create a large spawn.

For breeding with broodstock, we need to well prepared and constant monitor to ensure the broodstock is readying for mating. Let take breeding Betta sp. as an example. For pre-spawning, we need to find the suitable broodstock that match our intention quality characteristics for next generation and condition both fishes. Both fishes need to be feed adequately and flare each other from time to time. Once both fishes are ready, we need to setup the spawning and breeding tank to the right water quality, temperature, and hideout places for the female. During spawning, both fishes should be left alone and not to be disturbed and only need to be checked daily to make sure there are eggs. Once we have a spawn, the post-spawning start. The female is removed from the breeding tank followed by the male once the fry start free swimming.

In a growing tank for Betta sp., once some fishes have reach the juvenile or fingerling stage, there will be some fighting and aggressiveness behaviour. We need to jar these fishes immediately to prevent further injuries and thus may cause these fishes to succumb to diseases.

Just like human, fish also succumb to stress. There are many factors like outsider disturbance (when new fishes are introduced to the community tank) or environment factors like water quality, lighting, or food. Stress will cause low immunity and this allow bacteria and parasites to infect these fishes. We need to constantly monitor for disease symptoms although some are just false positives. But the common symptoms are there like inactive, low diet, swollen body part, sinking at the bottom of the tank, floating at the top of the tank, and many more. Immediate correctly actions need to be taken. First, if the fish is within a community tank, immediately quarantine and isolate the fish. Next, determine the type of possible disease and apply medication as need and frequent water changes.

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