RAISING TILAPIA AND OTHER FISHPOND TIPS

Earth Flavor in Tilapia

From March to August, it is common to find freshwater tilapia to have a taste like soil. It was researched on and found out that at UP Los Banos and SEAFDEC, Iloilo, that this caused by a kind of water plant or seaweed that the tilapia eat.

This earthly taste can be removed if the fish is soaked in pure lambanog ( coconut or palm wine) one hour before cooking. At SEAFDEC, the fish are raised first in a tank where they are deprived of food for six hours, to cleanse their intestines. Then these are transferred to another tank for 3 days, where the water is changed several times until the earthly taste is gone. This lasts from one to two weeks.


Good Breeding for Fish

To breed, the following should be considered:

1. The depth level of the pond must be lower that that of the sea or river to allow water to enter the pond at low tide.
2. The bottom of the breeding pond must consist of lime or compost, about 16%.
3. The pH must be between7-8.
4. The bottom earth must be clayey so as to retain water.
5. There must be two outlets to facilitate the entrance and outgoing of water.
6. One part of the bottom must be a little higher than the other side to make harvest of the fish easy.
7. Dig canals around 15 cm. deep around the pond for water to flow in. This will provide outlet for dirt and other things that may fall into the dike.
8. The dike should be strong enough against pressure of water from the crabs and eels thay may destroy and enlarge its holes, and high enough to protect from the overflowing during strong rain.

Lime for the Fish Ponds

Fish raisers have learned that the application of lime on fish ponds help a lot in the growth and reproduction of the fish therein, especially in water levels that have low calcium content. Like the application of fertilizer, lime is applied on the ponds. The most commonly available are those used on land-ground lime, and either calcite(CaCO3) or dolomite (CaMg(CO3)2).

As early as 1975, it was seen that plants growing in the ponds with lime flourished and the fish increased by 25%

Acidic Fishpond

After a strong rain, it is common to see dead fish floating on fish ponds. This is because of poisoning fro the acid coming from the pond bottom. This is common among soils that contains much sulfur of sulfide compound. When this kind of soil is exposed to the air in summer, its sulfur content mixes with the oxygen in the air and becomes poisonous sulfuric acid lethal to even humans.

When it rains, the water becomes poison to the fish because acid in the water activates some substances like iron and aluminum which mingles with water. In such cases, water in the fish pond should first be analyzed at the Bureau of Soils. The remedy for this is to apply lime and animal manure to counteract the existing acid.

source:elgu2.ncc.gov.ph