Construction of Fish Pond Around House

Many viewers have asked for more information on the fish tank close to my house. I shall speak about it today, in detail, drawing from our experience of maintaining it. Before that, let me clarify a point I made two weeks back about the K-Rail project. One of the major criticisms it provoked was regarding the anguish of the people who lose their property. I understand it perfectly because this is the tenth house I’m staying in. I had to sell off my house as well as my ancestral house in my native town when I realized that I would not be going back there at all. For nearly 40 years, I have been living outside the town I was born and raised in. I retained the property there for 25 years in the hope that I would return. But finally I had to sell it. I have had to live in different houses before coming to this one. My daughter’s regret is that she has no memories of having spent her childhood in any house for a considerable length of time. By the time we constructed our house, she was 12. Until then, we had been moving from one rented house to another. So, I understand the issue.

The second point is with regard to compensation. Often, in our state, we get very little value for our landed property. However when we try to purchase land, we do not get it at fair value. The solution lies in slashing tax rates, and fixing the price of property in a realistic manner. But that is not likely to happen in the near future. Therefore, those who stand to lose their land should be given either another plot or enough money to procure one before any such project is undertaken. Here, we are talking about the loss of people’s life savings. It is my strong opinion that adequate compensation should be given to people before they are evicted from their homes.

Now, to my topic. Two years back, we went to a forest created in Pichandikkulam near Aravind Ashramam in Puducherry. It was planted by a Britisher. I forget his name and the acreage of the forest. The forest was 47 years old then. When the Britisher first reached there, it was an arid piece of land. There was not a single tree in sight. Today it is a lush forest, created not in Miyawaki style, but following the traditional method. It took the forest nearly 50 years to look like one. The Britisher has put up houses here and there, and each has a water trough – one foot deep and one foot wide – running all around it. When I asked him about its purpose, he said it was meant to slake the thirst of friendly snakes that came by. The snakes would drink water and go back without crossing over into the house. It also helped keep ants and centipedes away.

Here, for entry into the house, the steps have been constructed in such a way that they have no contact with the building. You can see that from the close-up shots. The gap prevents crawling insects from entering the house. But ants come inside through the pillar supporting the solar panels, the drain pipes, and branches of trees. If those pathways are completely blocked, their entry can be prevented. Mice come into the attic, clambering over the cables and electric wires. But we are able to keep away these small crawling insects.

If we have such a structure, we will be able to grow fish. Secondly, it provides an opportunity for children to learn more about aquatic creatures. The water trough at the Britisher’s house was one foot wide. Here, we stretched it to two-and-a-half feet. A friend of mine suggested that we have it one metre wide because that will help fish turn about easily. He believes that circular movement improves their growth. I don’t understand the logic but those who grow fish say they prefer ponds which give the fish ample scope for circular movement. I have no experience in this field. The water trough already covers 350 sq. ft. and if I were to increase the width by another foot, the total area would be 450 sq. ft. That means, roughly one cent of land will be set apart for the fish pond alone. If I increase the depth further, I will be able to grow more fish. But that may prove dangerous if there are children in the house.

Many types of plants have been placed inside the trough. This one is the lotus plant inside a pot that has been inserted into a bucket. A stone has been placed so that it remains there itself. The stem will rise in search of sunlight, and eventually blooms will appear. We have placed the plot to the side so that it gets enough sunlight. I’ve also placed mangrove plants here. Generally, they grow in brackish water. But my friend Cherian Mathew brought me a couple of saplings of certain varieties that grow near lakesides. A botanist-friend of his had gifted them, and told him that they may grow in fresh water as well. I planted them in this trough two weeks back. They have not dried up.  In fact, they have put out new leaves. But I don’t think they will grow as much as the rest of the plants here. Or, as robustly as they would near lakesides or in estuaries.

It is said that long back the entire coastal belt of Kerala was fringed with mangroves. Their leaves have high protein content. I am told the fish in the Vembanad lake grew in huge numbers because they lived close to these mangroves, and ate those leaves. An entire ecosystem developed around the mangroves. Otters living in such places used to feed on fish but they were killed for that very reason, and when their numbers dwindled, the number of fish also diminished. That was because otters could catch only the sick fish. In this manner, the otters had actually prevented the spread of diseases among the fish. If we see otters only as predators and kill them, infections among the fish will spread and destroy their numbers. Thus the mangroves sustain an ecosystem. Unfortunately, we are wiping them out of our coastal areas. If we help in their regeneration, we will be able to prevent sea surges and other natural catastrophes from affecting us, to some extent.

Now, back to our subject. One of the issues we have to handle is feeding the fish. I have introduced a few large-size varieties, and they seem to be growing fairly well, like Rohu, Tilapia, Carp and so on. We removed the colourful varieties and introduced a few native ones. When the native fish began to disappear one by one, we thought the others were responsible. But quite accidentally we spotted a crab in the trough. It had either come on its own or someone had put it there. When it caught the small fry, we didn’t notice because it was concealed between and beneath the leaves. Only when the large, coloured ones were caught did we see it. We then removed it from the trough. Since then we have not introduced native varieties of fresh water fish like Orange chromide, Asian striped catfish and so on. Maybe sometime later, I should.

Now, to tell you about water plants. That is water bamboo. And that is water hyacinth. It is seen in profusion in the Alappuzha area, and its flowers are lavender in colour. I had mistaken it for oval leaf pondweed, and was corrected only recently by a botanist-friend. The buds have emerged, and soon the blooms will appear. They are very beautiful. I’ve seen them fill entire lakes. This is Azolla. We’ve prepared a couple of trays, and placed Azolla in them. The floating tray is very easy to make. All you have to do is join four PVC pipes to form a frame, and fix a net on it. Spread the Azolla on the tray and they will grow. It is a kind of algal bloom that has high protein content, I  am told, and can be used to feed fish, chickens, ducks, cows and so on. If you introduce Azolla into a small pond, it will cover the entire surface in a few days. They spread fast. The fish eat Azolla but not when it is inside the tray. Whenever necessary, we can drop Azolla into the water to feed the fish. There are a couple of other water plants too. That is Indian pennywort that is commonly seen in paddy fields. There are two varieties of this plant. This one has large leaves. The other variety – with smaller leaves – is seen to grow on soil. The big size and glistening surface of the leaves may be because they grow in paddy fields. It has medicinal value too, and is used to cure intestinal diseases. This plant too can be grown in trays. This is brahmi or water hyssop, said to be good for improving our memory power. It grows in paddy fields and water-logged areas. Like the other plants, water hyssop too can be placed on a tray, and left to float in the trough.

Frogs come here and lay their eggs. If we sit here, we will be able to watch the life cycle of the fish – as they grow from egg to small fry. The mother fish will swim above them in circles, like a helicopter, and not permit any fish to come near them. In the next stage, the small fry will swim above, and the mother keeps watch from below. This applies to only certain species of fish.

As for cleaning up the water trough, leaves falling from the nearby trees pose a major problem. Keep a net handy to remove them. If that is costly, one can be made at home by bending a wire and fixing a net to it. The readymade net makes our work simpler. But we can make big ones by ourselves without incurring much cost, and remove all the fallen leaves.

With regard to fish food, it is available in the market. Besides, like Azolla, leaves of Colocasia can also be given. Put a Colocasia leaf in the water, and in two days all of it will be consumed except the veins. Colocasia grows abundantly in Kerala, and can be raised in pots too. Feeding the fish with these leaves will bring down the cost too.
 
As far as maintenance is concerned, the greatest number of queries I get is about the frequency of cleaning. Fish droppings are a big problem. When I see the sheer volume of fish droppings, I sometimes feel fish can compete with cows! But fish poop can be used as manure. A filter can be fixed in this trough.  I haven’t done it yet. I plan to fit it soon. That will keep the water cleaner and then I will be able to grow more fish. This water trough has been divided into three sections. We did not have the partitions in the beginning. They were installed only recently. If the water level is brought down, each of the sections will be like a separate receptacle of water. Fish in one section will not be able to swim over to the other. For the purpose of cleaning, we confine all the fish in two sections, and drain the third. After that is thoroughly scrubbed, we repeat the procedure to clean the other two. Besides, there are outlet pipes fixed to each of the three segments in order to prevent water spillage when it rains. A net covers the mouth of the outlet pipe. The excess water flows automatically to the plot below. In order to wash the trough, we have to open the water tap. That will ensure the draining of fish droppings as well. One of the conveniences of this house is that it is at an elevation. So draining the water does not pose a problem. After all the soiled water has flowed to the forest plots below, fresh water is pumped into the trough, segment by segment. You can see each of them. After the fish are put back, more water is poured so that the water level stands three inches above the partition walls in the trough. Now the fish will be able to swim all around without facing any obstacles. The cleaning needs to be done only once in two months. We don’t do it more frequently here, and haven’t faced any problem because of that. Since we have so many plants they may absorb manure from the fish droppings. But I am not sure of it. That is for botanists to confirm or deny.

If you have nothing special to do, you can let your imagination take wing, and see this water trough as an ocean and the fish as whales. You will be able to while away your time pleasurably. It is a means of entertainment. And, for children, it offers plenty of opportunities to learn about water plants, aquatic animals and so on. This contraption can be accommodated in schools too. Its shallowness will prevent accidents, and children can safely learn about the life cycle of fish. My request is that a project of this kind in schools should be given serious consideration.