Evolution Aqua FAQ's
Cascade has supported the many products developed by Evolution Aqua since its conception. Cascade has been appointed a “Master Dealer” at both its sites in Manchester and Harrogate. We have working examples at both our sites and trained staff to answer all your questions. Contact us here MANCHESTER or HARROGATE. Here are a few frequently asked questions.
Is there settlement in the Nexus biostage?
If the outer Kaldnes chamber is aerated at the recommended levels we have found that virtually no settlement occurs so discharge is not required on a regular basis.
The recommended levels are as follows:
- 40 litres per min with 100 litres K1
- 80 litres per min with 150 litres K1
- 120 litres per min with 200 litres K1
How is the amount of Kaldnes I require in my Nexus calculated? Is it based on the volume of water in my pond?
It is based on the amount of food you expect to feed to your Koi. The Nexus is supplied with 100 litres of K1 media; which is sufficient to cope with the biological loading from feeding 0.5kg of food per day. If you expect to feed more than this then simply add further media up to the maximum loading of 200 litres of K1 per Nexus unit. The aeration also needs to be increased to ensure the media remains as a fluid bed.
If I add chemicals to the pond, will they affect the Nexus unit or the Kaldnes media?
The Nexus body and Kaldnes media are both made from tough long lasting polyethylene. This is totally impervious to the normal range of chemicals one would expect to encounter during treatment of pond parasites.
The Answer and most of its components are made from 316-grade stainless steel, which is resistant to rust and the normal range of chemical treatments.
Does it need cleaning and maintaining or is it zero maintenance?
The unit is advertised as 'genuinely low maintenance.' The screen although self cleaning, will with time lose performance due to bio film build up. So far, the average time that 'The Answer' will run without cleaning is between 8 to 10 weeks. This then reduces to 12 to 14 weeks on the second clean due to the pond environment being improved. The most efficient and best way to clean the screen is with a cleaning agent, which is available from E.A. and the process takes 15 minutes. We suggest cleaning every 8 weeks in any case.
What maintenance does the Nexus require?
Ideally in summer under normal stocking levels a quick daily discharge of the central chamber is all that is required. This should remove most of the deposited solids. On a weekly or twice weekly basis it would be beneficial to totally drain the central chamber and flush out the remaining debris.
If the Answer is fitted the only maintenance required is to monitor the Answer performance and clean the screen every few months to remove the build up of bio film.
If the Nexus is used with the central foam block this needs to be cleaned at regular intervals depending on the pond conditions and stocking levels.
The exit foam with the Answer fitted requires virtually no cleaning. It is fitted to filter out the sloughed off bacterial cells from the Kaldnes media mainly and to trap any particles smaller than 100 micron that have passed through the Answer. A more regular cleaning may be required if the Answer is not fitted.
Why does Kaldnes K1 media float and not sink?
When first loaded into your filter the Kaldnes floats because tiny air bubbles are trapped within the 4 central chambers of the media. The surface tension of the new plastic media needs to be reduced before it will attain neutral buoyancy. In fresh tap water this process can take up to four of five days before the K1 circulates within the filter chamber correctly. In an existing mature system where fish waste present this process can take as little as 2 hours.
I have just fitted my Nexus filter and Answer. The pond is running and I have re-introduced my fish. Do I need to start the Kaldnes media off by introducing a filter bacteria starter culture?
The addition of a starter culture, although not strictly required will aid in the start-up process of your filter.
What do I do if a unit blocks causing the prime vortex to overflow?
In the event of a unit blocking causing the prime vortex to overflow, please check the following:
- Power supply to pump.
- Remove the pump and check it is operating properly. Take care when refitting the pump that is correctly located in its housing.
- Make sure that you have not overloaded the prime with too much waste matter. This has happened to over enthusiastic keepers doing demos at home and putting in a full bucket of solid waste to see what it will handle. Be realistic, the unit will handle the dirtiest pond but there is a limit Make sure you have not exceeded the maximum flow rate for the unit.
- Make sure the boot is fitted properly and not leaking in dirty water causing the unit to block from inside.
- Remove completely the unit and manually check the rotor arm is spinning inside by gently placing your hand in and moving the arm slowly.
- If none of the above resolves the problem, either ring the office or return the unit with a written account with what has happened.
There is no water coming out of the rotor arm so my screen blocks straight away.
Firstly check the fuse in the plug and ensure there is an electrical supply to the backwash pump. If this is ok you should feel a slight vibration from the pump.
Secondly check the rotor arm nozzles for blockages. Thirdly the unit is possibly air locked. To remove this loosen the central star nut on the lid to ensure there is no air trapped in the unit. If there is no air in the unit and no vibration is felt from the pump the impellor is possibly obstructed. Remove the pump and clean. Do this by removing the four screws holding the pump to the unit and withdrawing the pump. Check the impellor and waterways for obstructions. Clean and re-assemble. Refit the lid and bleed all air from the unit. If the impellor is free of all obstructions but still does not rotate the pump is faulty and the unit should be returned to us.
The rotor arm is not spinning but water is coming out.
Firstly remove the lid completely and see if the rotor arm spins freely. Possible causes of a stuck rotor arm are either a bent screen or seized central bearing. If the screen is ok but the rotor arm still will not turn check the two nuts (one silver, and one brass locknut) on the central rotor shaft have not been over tightened during assembly. If so completely remove the brass top nut and loosen the silver nut so that the arm freely spins. Hold the silver nut with one spanner and re-fit the brass nut and fully tighten down on to the silver nut. Re-fit lid and switch unit back on after bleeding all air from the unit.
The water level in the tank after the Answer is getting lower but the Answer is running correctly.
The screen may need cleaning. Bio film can build up within the screen and reduce its ability to pass water at the stated rates. Use a steam cleaner or caustic soda to do this. Mix to a solution following the pack instructions. Either remove your Answer or screen from the system and either brush or spray this onto the screen and leave for 15 minuets. Thoroughly wash off to waste with a hose or power washer and re start the system.
Or if the Answer is fitted in an inverted manner does the exit pipe work after the Answer form an inverted ‘U’ bend into the second stage of the filter. If so it may have an air lock in the pipe partially reducing the flow. Fit a small air release tap in the pipe at its highest point.
If the Answer has been fitted into a horizontal flow, multi chamber filter system with weir type baffle plates ensure that the weir plates have been reduced in height to account for the Answers reduction in head throughout the preceding chambers. NB: When using caustic soda, ensure you follow the safety instructions on the packet.
I have noticed from the latest publications that the Answer is now available with 100 and 200-micron screens. If I change to a 200 micron screen what are the advantages and disadvantages.
If the flow rate through your Answer with the standard 100 micron screen is insufficient you could consider changing your screen from a 100 to a 200-micron size. The larger micron screen also requires far less maintenance for visibly no deterioration in water quality. Also certain high protein foods tend to produce a silk residue, which does have a tendency to clog the finer screen.
I have a traditional 3-chamber vortex filter system at present with central 4-inch exit pipe work. How do I best fit the Answer and which of the two biological chambers should I convert to Kaldnes media.
The Answer is easily fitted into a standard central exit vortex. You will have to alter the length of the central pipe so that the Answer sits well under water. The most important change we make in this installation is to the inlet pipe work from the pond to the vortex. We need to convert the inlet pipe from a horizontal tangential flow to a vertical one. Do this by fitting a 90-degree bend with a short vertical pipe. The top of this vertical should be at mid Answer screen level. This has 2 effects, it stops the spin of the water caused by the tangential entry and secondly it creates a downward flow of water towards the screen of ‘The Answer’. This effect means that every time a particle is removed from the screen, instead of hitting it immediately after the pulse emitted by the arm has passed, it drops down slightly. This removing and dropping of the solids terminates when they reach the lower surface of the unit into what is effectively dead water. Once here, there is no way back and they drop motionless to the bottom of the tank where they can be discharged to waste.
If you intend to convert one of your biological chambers to Kaldnes media the first chamber is the best one to choose.
Since fitting my new Answer into my existing vortex I have noticed that the collected debris does not settle in the bottom of the chamber anymore. It remains in suspension throughout the whole vortex chamber.
Alter the inlet pipe work from the pond to the vortex. From a horizontal tangential flow to a vertical one. Do this by fitting a 90-degree bend with a short vertical pipe. The top of this vertical should be at mid Answer screen level. . This has 2 effects, it stops the spin of the water caused by the tangential entry and secondly it creates a downward flow of water towards the screen of ‘The Answer’. This effect means that every time a particle is removed from the screen, instead of hitting it immediately after the pulse emitted by the arm has passed, it drops down slightly. This removing and dropping of the solids terminates when they reach the lower surface of the unit into what is effectively dead water. Once here, there is no way back and they drop motionless to the bottom of the tank where they can be discharged to waste. Ensure that there is at least 8 to 10 inches bellow the Answer to allow this settling to be effective.
I have one strong pulse of water coming from the rotor arm on my Answer and one weak one.
You either have one of the two nozzles blocked with debris or one is split. If the problem is a blockage strip the unit and clean. If you have a cracked or split nozzle return the unit to us for repair.
The level in the tank containing my Answer is too high and overflowing but the Answer is running correctly.
Firstly make sure that the flow rate you are trying to pass through the Answer does not exceed the stated maximum flow rates for your model. Secondly consider cleaning the screen. Bio film can build up within the screen and reduce its ability to pass water at the stated rates. Use a steam cleaner or caustic soda to do this. Mix to a solution following the pack instructions. Either remove your Answer or screen from the system and either brush or spray this onto the screen and leave for 15 minutes Thoroughly wash off to waste with a hose or power washer and re start the system. NB: When using caustic soda, ensure you follow the safety instructions on the packet.
My Answer is running but I have to clean the screen every 3 days or so to maintain the flow rate and to prevent it from blocking.
Bio film can build up within the screen and reduce its ability to pass water at the stated rates. Use a steam cleaner or caustic soda to do this. Mix to a solution following the pack instructions. Either remove your Answer or screen from the system and either brush or spray this onto the screen and leave for 15 minutes Thoroughly wash off to waste with a hose or power washer and re-start the system.
Try cleaning the screen with caustic soda.
If cleaning does not solve the problem the pump may be blocked, or the nozzles may be blocked or split. Follow the dismantling and cleaning instructions. If the pump and nozzles are ok check that the black pump housing and fittings situated below the Answer are not leaking through their O-ring joints. This is done by running the unit submerged and feeling to see if there are any water jets. All these joints should be watertight.
Due to our ongoing research we have designed a modification applicable to 410 and 325 models. This would benefit models fitted in an inverted manner where performance is poor. Please telephone us for instructions to see if your model has been modified during production or not. NB: When using caustic soda, ensure you follow the safety instructions on the packet.
My pump keeps getting blocked with snails, frogs or blanket weed. How is this happening? Are they getting through the screen?
No they are getting back into your Answer from your biological stage. When you empty your vortex chamber you are allowing old debris to siphon back into the inside of the Answer. The solution is to fit a slide or ball valve after the Answer. Close this valve prior to any discharge operation.
I have just bought a Nexus filter unit. What base dimensions do I need.
Before installing your Nexus filter you need to prepare a base of level solid ground with minimum dimensions of 1.3m x 1.5m this will allow easy access to the discharge valves and for easier maintenance etc.
The base should be approximately 100mm thick. And must be perfectly level preferably made of concrete. Although decking, paving slabs or gravel would be sufficient as long as the Nexus sits level and is not allowed to sink into the ground under the weight of the water.
For gravity fed systems the upper surface of this base should be 954mm below the proposed final surface water level of the pond.
For pump fed systems the unit can be any height above the surface water level (subject to the max. performance of your chosen pump being able to deliver enough flow), allowing adequate gravity return to the pond. However, care needs to be taken that the top of the Nexus is at least 500 mm higher than the discharge point of the gravity return pipe into the pond or waterfall etc.
If my Answer cannot be fixed by myself on-site, what do I need to do when returning it to yourselves for repair?
Complete a form either online or over the phone to us. Name, address, serial number etc, we will issue you with a job number and arrange collection. You must ensure that your Answer is securely packaged and ready for collection.
Does it need cleaning and maintaining or is it zero maintenance?
The unit is advertised as 'genuinely low maintenance.' The screen although self cleaning, will with time lose performance due to bio film build up. So far, the average time that 'The Answer' will run without cleaning is between 8 to 10 weeks. This then reduces to 12 to 14 weeks on the second clean due to the pond environment being improved. The most efficient and best way to clean the screen is with a cleaning agent which takes about 15 minutes. We suggest cleaning every 8 weeks in order to keep the unit running at peak efficiency.
Why should the first chamber be used for Kaldnes K1 media?
All inlet, outlet and discharge pipes first need to be protected against loss of media. We normally achieve this by fixing a pvc or plastic mesh screen over them and gluing or fixing in place.
Fitting Kaldnes
Next an air ring, diffuser or air stones need to be fixed in place at the base of the chamber. This ensures a complete and constant mixing of the media throughout the chamber. You then need to calculate the volume of the chamber to ascertain the amount of media required. See the formula.
How do I calculate the volume of my chamber?
You need to calculate the volume of your chamber in litres. To calculate the volume of your chamber in square inches multiply the length by the breadth by the depth (L x B x D). Then multiply by 0.0164 to give the number of litres. Centimeters are easier, simply divide total volume by 1000 to give litres.
It is possible to use no less than 30% to a maximum of 67% of this volume with K1. We recommend an average of 50%.
Examples:
Tank 24" x 24" x 24" = 13,824 square inches.
Multiply by 0.0164 to give 227 ltires volume of the chamber. Then multiply this by 50% to give 113.5 litres of media (recommended).
For a 24" vortex with a straight side 24" depth to the cone of this would be 12 (half its diameter) x 12 x 3.14 (pi) x 24 (height) = 10,581 square inches.
10,581sq" x 0.0164 = 178 litres.
= 89 litres of media at 50%
If you wish to use part of the cone then please call us for further advice.
Can the return to the pond from the Nexus be slightly (12") below water level or must it be open?
If the installation you are describing is a pump feed system, the return pipework from the Nexus can be returned to the pond under the water surface. As long as you have a head of at least 500mm above the pond water surface at the outlet of the Nexus.
Why do you recommend that the inlet to the chamber housing 'The Answer' needs to be piped upwards and remove any vortex action?
This actually provides 40% of the efficiency and benefits of the unit. 'The Answer' will take out and settle an amazing amount of waste, especially fine solids, which in the past have gone straight through into the biological chambers. If 'The Answer' is retro fitted into a vortex and the vortex action is not removed, the fine solids cannot settle and remain in suspension, attacking the screen simultaneously. This means that there is little or no settlement and to clean the tank, the whole volume of water has to be dropped. By bringing the water in vertically and level with the middle of the unit, a downward flow effect towards the filter is caused. The particles will now hit the screen, get knocked off and drop a little due to the direction of water trying to enter through the screen The particles when they reach the lower surface of the unit have no alternative but to drop to the bottom of the tank where a dead area of water has been created. It is impossible for them to get up again. By doing this, the screen needs less cleaning as it isn't constantly being hit with the same debris and there is considerably more settlement allowing easier sumping off to waste.
What are the most typical problems that customers have had so far after fitting an 'Answer'?
There have been only a few problems but the most common are:
- Not fitting the unit properly as per instructions.
- Not tightening the two jubilee clips on the rubber connector.
- Not changing the inlet pipework.
- Leaving too little settlement space below it causing all solids to be in permanent suspension and overload the screen.
- Exceeding the recommended flow rates.
- Using push fit pipe which allowed waste to track through the joints.
- Creating airlocks in pipework that they fitted to accommodate 'The Answer'.
In a vortex or settlement tank, where is the best place to mount 'The Answer' in relation to depth?
If the exit port is high, 'The Answer' will be mounted upsidedown. Ideally it should be mid water or failing that, higher.
What flow rate can 'The Answer' 410 handle?
'The Answer' 410 is guaranteed to handle a maximum of 13,000 litres per hour when it is retro fitted into an existing system. Problems may arise if more water is passed through as the pressure of the backflushing effect cleaning the screen is reduced. An 'Answer' in the Proline series handles 13,000 litres per hour, turning the pond over once every 2 hours. This as our tests have shown is a good balance for the retention time in the bio chamber.
What are the minimum dimensions of a prime mechanical container required to fit an 'Answer'?
The Answer' as shown in this leaflet is 410mm diameter and 336 mm tall. The container needs to be a minimum of 620mm wide and have a settlement area of at least 250mm below the lower surface of 'The Answer' screen.
Can 'The Answer' be fitted on its side?
Yes, but it is not 100% efficient and the settlement effect is reduced. Waste spends too much time on the screen instead of dropping away and this causes more fouling and the need to clean the screen becomes more frequent. Also particles in permanent contact with the screen can macerate and breakdown eventually being downsized so they can pass through the screen.
Does 'The Answer' block?
The unit will not block if fitted correctly, used in the recommended conditions and flow rates. We advertise it as 'genuinely low maintenance,' that being a 15 minute cleaning process every 8 weeks in normal conditions. It is not a miracle that can be fitted and forgotten about but with minimal care and attention, the results as already being testified to, are 'breathtaking.' 'The Answer' and pump carry a full 5 year guarantee and the tanks carry a lifetime guarantee.
How does it cope with the dreaded blanket weed?
'The Answer' if fitted correctly in the right environment will cope with blanket weed and settle it out. The problems occur when the next frequently asked question is not adhered to.
Does the pump on 'The Answer' circulate water through the system?
No, the backwashing pump only draws and delivers water inside the unit, which cleans the screen. It does not circulate water through the system.