Allotment Articles 2.
10 Problems With
1 Concrete ponds often leak after a few years. If the pool has cracked you can buy a repair compound which has a waterproof additive mixed with the cement compound. Sometimes this will cure it, but if there is subsidence on the pond then the only answer may be to install a liner of some sort. Sometimes the concrete becomes porous, or the old coat of sealant peels off. In this case brush it down with a wire brush and coat with a fresh coat of pool sealant.
2 Green ponds are a perennial problem. This is basically due to too many minerals in the water which acts as food for the green single celled plants called algae that turn the water green. It is a myth that a pump will clear the water, but installing a pump does enable you to add a biological filter and U V system. The filter must run 24 hours a day throughout the season and takes about 8- 10 weeks before it becomes fully functional, although this can be speeded up by the addition of special bacteria in solution. The natural way to clear green water is with the addition of more plants, especially oxygenators. Chemicals are another solution as many algicides are now available. The addition of a little pack of Barley Straw is also supposed to work.
3 Overfeeding can result in pollution of the pond and ultimately in fin rot. If the pond is cleared, the fish can be treated with any proprietary fin rot remedy and in most cases fins will re-grow. To cure overfeeding problems use floating foods so that you can see what is being eaten and you can easily fish out any uneaten food. The addition of a scavenger fish, such as a Tench, will help to remove unwanted rubbish and so cut down on pollution.
4 Large Golden Orfe often die in hot summer months. This is due usually to oxygen shortage. Orfe are a river fish rather than lake, or pond so they have a high oxygen requirement and when it is hot the water holds less dissolved oxygen so they suffer. The answer to this is quite simply to have a pump running, especially on hot stormy summer nights.
5 Small fish often disappear without trace. This is usually because a bigger fish has eaten them. The simple rule is never mix big fish with little ones. Also a large catfish in a pond with other fish can well lead to problems, as they are well known for their aggressive tendencies.
6 Oxygenators often get eaten when put into a fishpond. All the carp species, goldfish, Sarasas, comets, Shubunkins and Koi love to eat green plants leaving you with just bare stalks, or even less after a few days. The only consolation is that it is good for them acting as a valuable source of nutrition. The way to stop them being eaten is to make a cage out of plastic coated wire mesh (not galvanized) and let the plants grow through it. Koi can be a real problem with any plants and generally the only plant that can be successfully kept in a Koi pond is a lily and even this will be dug out of its pot until it is well established.
7 Fish sometimes die a few days after cleaning out the pond in summer. The reason for this is that the pond water was quite warm before the fish were placed into the cold tap water that it was refilled with and they received a chill. This usually causes white spot that is highly contagious and can lead to fish dying.
There are several proprietary medicines which will effectively cure white spot in a few days, but the best solution is when transferring the fish into the newly filled pond, float them in a bag of the old water for 1/2 hour to acclimatize them.
8 Sometimes a waterfall is added to a pond and the water level goes down as if it has a leak. This is usually caused by incorrect alignment of the waterfall, so that drips are running around the edge and not going into the pond. A very tiny V cut into the waterfall either side of the drop edge will also help to cure the problem.
9 Fish suddenly dying in a new concrete pond, or after a concrete waterfall has been added to a pond is usually caused by the presence of lime in the water. It is most important to treat all new cement work in and around a pond with a neutralizing compound, or cover it with a plastic paint. The addition of a P H buffer can also be used if it is only a small amount of cement involved.
10 Blanketweed is a perennial problem with most ponds at some time or another. This is a long filamentous algae best described as looking like green candyfloss. It chokes pumps and all plant life, although it is beneficial to some extent as when you have blanketweed, your water in the pond is very often crystal clear. It is best removed manually with a stick and then poisoned with a selective weedkiller. This is not as dangerous to other pond life as it sounds if the instructions on the packet are followed carefully. Various other chemicals are available which restrict its growth by altering the chemical structure of the water. Alternatively, some fish are said to eat Blanket weed, although in practice they will only keep it in check at best. Large Carp will nibble at it, but Grass Carp are probably the best fish for the job.