General Pond Question and Answers

A: Most healthy pond fish should have sufficient body fat on them during the summer months to survive for 2 weeks without being fed. Any longer means that some form of feeding is required. If you have equipment running (pumps, filters etc), then I would strongly suggest that you impose on a neighbour or relative to visit the pond ideally daily and certainly every 2 days. If this is possible then they can obviously feed the fish, but ensure they fully understand the equipment and how much to feed the fish. It is not at all uncommon for good intentioned neighbours to over feed the fish. If this is not possible then there are food blocks, which can be put in to the pond. These are fine for smallish ponds and goldfish but no good for Koi ponds.

Links: Koi and Goldfish Foods - Pond Fish Feeding Accessories

A: The two most common problems experienced with these plants are rippling water and depth. Lilies do not like rippling water, it causes their leaves to initially darken around the edges, referred to as burning, and then slowly the whole leaf dies. All varieties of lilies have a preferred depth, if the water is too deep then the leaves will struggle to reach the surface and the plant will die. With this in mind the plant should be located at a suitable depth even if this means putting on top of a plinth and well away from any fountains, waterfalls or filter outlets. If the pond is well stocked with plants and you have a limited number of fish then it would be worth adding a fertiliser tablet to the soil around the plant.

Links: Pond Plants and Accessories

A: Both options have their own merits and pitfalls. In general an above ground pond is harder to construct, but easier to look after and enjoy once constructed. During construction a raised pond will require less digging, but will require a double skinned wall (2 walls of bricks tied together). Therefore the project can be expensive and take longer to complete. On the positive side, once constructed a raised pond will be safer, because it is harder to fall in to. It will be easier to maintain, because the pond is it at a higher level, and it can be viewed more easily with built in seating or simply by sitting on the wall. Conversely raised ponds are more exposed to the elements, and can suffer more extremes of temperatures, which may affect the health of the fish. It can also be very difficult to locate and hide filtration equipment if required.

Links: Pond Liners and Accessories

A: When making a solid water fall such as the one you describe, the first thing to consider is that you require a solid base, this is to avoid the possibility of settlement, which could wreck all your hard work. Yes the slabs should have a downward angle, 5 degrees should be adequate, this is not only to allow the water to flow down them efficiently, but also to help prevent water from trying to travel back under the slabs. Ideally the slabs should have a ridge on the underside running along the edge that the water will fall off. This will further help prevent the water trying to travel back under the slab. We would recommend that the slabs over lap one another and the pool by 75mm (3"). As you may have gathered from the advice above, their is a significant risk of leaks on a purely Slab and Concrete waterfalls. We would recommend that the construction be built on top of a pond liner, so that even if the waterfall does spring a leak the water is captured. With regard to the water flowing away from the pond, if you choose to use a liner then this should not be a dramatic problem. Other than this either the slabs need to be contoured to channel the water flow or the slabs will require an edge. In terms of flowrate and the sizing of a pond pump, one of the hardest problems is visualising the flowrate you require. To help with this we use these guidelines.
• To create a 12mm (½") depth of water 30cm (12") wide a flow of 4500 litres per hour (1000 gallons per hour) is required.
• To create a 5mm (¼") deep sheet of water 30cm (12") wide over a waterfall a flow of 3600 litres per hour (790 gallons per hour) is required. This flow will create a solid wall of water 30cm (12") wide, from 30cm above the surface without the falling water breaking up.
• A standard open ended garden hose produces approximate 900 - 1100 litres per hour (200 - 250 gallons per hour).

Links: Pond Liners and Accessories - Pond Pumps - Pond Paint

A: I would suggest, being new to fish keeping, the best sort of fish to start with would be Goldfish and Shubunkins. These fish are relatively inexpensive and hardy and will also add some nice colour to your pond. It is also worth introducing a few bottom feeding Tench, which will help clear up any uneaten food on the bottom of the pond. It is common for people to fill the pond up with fish when they first start, but Goldfish and Shubunkins will only grow to the space available. It is therefore, far better to stock reasonably minimally initially and then let the fish grow to a larger size than you would normally achieve. If your pond is large enough and as your knowledge grows then you could look to introduce a few small Koi, which are generally more expensive, but can add a wealth of beautiful colour to your pond.

A: When introducing fish in to a garden pond it is important that you check the water quality first (Ammonia, Nitrite, Nitrate) with a pond water test kits, to make sure the water is safe for introducing new fish, if it is not the problem should be resolved before the fish are introduced. When buying fish from an Aquatic Retailer, always make sure they introduce plenty of oxygen in to the bag, this is both for the fish to breath during their journey and because they will need floating in your pond. When reaching your pond you should float the fish in the pond with the bag still sealed for approximately ½ hour. After which the bag should be opened and the sides rolled down (to create air pockets) and the bag should be topped up with a proportion of your pond water added to give a 75/25 mix. After 15 min's a further top should be done to give a 50/50 mix. Once this has been floated for 15 minutes then the fish can be released by submerging the bag just under the water and letting the fish swim out.

Links: Pond Water Test Kits

A: Whether you require a treatment when topping up your pond is a frequent asked questions. If the water authorities were only using Chlorine in our tap water now, then there would be little requirement too use a Dechlorinator, however, they now frequently use Chloramine. The difference as far as the pond owner is concerned, is that unlike Chlorine, which will naturally dissipate in 7 days, Chloramine can last for 30 days. This means that if the pond is topped up once a week then the level of Chloramine can start to build up in a pond. If in any doubt use a Dechlorinator which neutralises Chloramine should be used. If you have a filter system it is also a good idea to boost the bacteria colony at the same time.

Links: Tap Water Treatments

A: When using natural rock in a pond environment it is advisable not to use porous rocks such as limestone or sandstone as these leech pollutants into the water and can cloud the pond and alter its chemistry, most commonly raising the pH reading. Non-porous rocks such as granite or slate are ideal for natural looking water features.

A: The guarantees offered with liners nowadays cover the degradation (cracking/becoming brittle) of the liner by sunlight, they do not cover the more common dangers of puncture to the liner. The threat to liners comes from both above and below ground. Above ground the threat can be from Herons, Dogs, Cats and of course the stray spade. Below ground the threat is generally from stones and plant root systems. The more expensive materials such as Firestone EDPM Pond Liner, Greenseal EDPM Pond Liner or Butyl Rubber Pond Liners will generally be thicker and as such will be strong and less likely to puncture. You therefore need to weigh up the possible dangers to your liner before deciding what grade to purchase. If you are likely to experience any of the above problems then you should opt for Firestone, Greenseal or Butyl. If not then PVC should suffice.

Links: Firestone EDPM Pond Liner - Greenseal EDPM Pond Liner - Butyl Rubber Pond Liner - 0.5mm Aquaprem PVC Pond Liner

A: I am thinking of build a pond this year and have conflicting advice about how deep to make it. What is the correct depth? The intended inhabitants normally control the depth of a pond. Natural ponds intended for wildlife only, do not have a recommended depth, but because of the requirement for a beach (to allow the amphibians easy access) they generally start at nothing and run down to 450mm - 600mm (18" - 24"). Ponds intended for Goldfish, Shubunkins or Comets should have a reasonable proportion of the pond that is 760mm - 900mm (2½ft - 3ft). Where as Koi should have a good area of the pond which is 1200mm - 1500mm (4ft - 5ft) deep. These depths are required to give the fish space to exercise and to prevent the pond from changing temperature too quickly as this can have a damaging effect on the fish.

A: Generally to prevent pond water from turning green you require 60 - 70% surface cover. This can be achieved using Lilies, Water Hyacinths and Water Soldiers to name but a few of the selection available. By producing the shade in this way you not only cut out the amount of light reaching in to the water, but you also introduce plants which will compete with algae for the available nutrients.

Links: Pond Plants and Accessories - Green Water Treatments - Pond UV Lights

A: This is a frequently discussed topic in many aquatic centres. The problem is that unlike goldfish, Shubunkins and Saras Comets, Koi are bottom feeding Carp. This means that in the wild they would normally be rummaging along the base of a river disturbing the sediment looking for food. This natural habit when transferred to a pond often means that Koi end up substituting the base of the pond with your planting baskets and a Koi of 30mm (12") can easily turn over a small planting basket. I have also seen Koi appearing to munch on lily leaves but on closer inspection they have been eating the snails eggs laid on the leaves. The fact that they were not eating the leaves didn't help the plant though. However, this is not always the case I have visited many ponds that have a few Koi in them and plenty of planting baskets that are not protected. To try to minimise the affect Koi can have on the plants you need to prevent them from getting at the soil and make the planting baskets heavier. This can be done in one process, placing large fist sized pebbles on top of the soil, or removing a few centimetres of soil and replacing it with a layer of lime free gravel.

Links: Pond Plants and Accessories

A: It is not common for fish to not breed, but far more common for the eggs and fry not to survive, particularly in densely populated ponds. This is because the adults will eat them either as eggs or as they grow over the next year. If you would like to ensure that the next generations of fish survive, then you need to catch the eggs success fully and protect them from the adults. The first signs that the fish will be interested in spawning are a few single fish being chased around the pond by several other fish. This is the female being chased by the males, although it can look cruel, it is required to help stimulate the female in to laying her eggs. Once they decide to breed, which will only happens 2 or 3 times a year, the eggs will be laid at dawn, almost immediately the adults will start eating them. You therefore need to use some sort of catching devise, a variety of which are available on the market, and install this when you see the fish chasing one another and then get up early for the next several days. Once they have spawned the catching devise needs transferring either to and aquarium or tub filled with pond water or a floating cage in the pond. It is important that the eggs are well oxygenated, and therefore if they have been taken out of the pond, an air pump should be used to oxygenate and circulate the water. If the eggs are being kept in a floating cage in the pond, then this should be located near a good source of circulation. When the eggs hatch the fry should be fed on specialised food or crushed flake food. They should be kept separated from the other fish for 12 months until they are large enough to hold there own in the competitive world of your pond.

Links: Pond Air Pumps