Thoughts please on planned filter upgrade options

[ajb]

Questers,

I am looking at options for upgrading my filtration, and plan to make the changes next year (2010). I am interested in your thoughts on my options, and any other ideas you might have.

I include below some narrative and some pictures to help you understand where I am in the hobby, my current set up and what I want to achieve from the changes.

Regards

Adam

A little history:

My pond is around 20 years old. We inherited it when we moved into our house about 2 and a half years ago. It takes up quite a large area and to protect our young children the first thing we did was to drain it and put a fence around it.

In summer ‘09 we decided to get the pond going and enter the koi keeping hobby. So far, that has involved:

- fibre glassing the pond
- cleaning out the whole filter bay so it was squeaky clean. We cleaned all the media, then replaced it where we found it. The filter was seriously mucky - I was literally shovelling out spade loads of thick muck. The flocor was like a bird seed cake - solid.
- I added 50lts of new ceramic media in the last bay
- I bought 5 koi from Cuttlebrook at their harvest in September

My pond and set up as it currently stands:
Summary of the pond:

- Total water volume (pond + filter, excluding header pond) = 19,500 litres (c4300 gallons)
- depth varies throughout the pond, max pond depth = 4.5ft
- quite a large surface area - each inch rise in water after all the slopes etc are under the water = c. 1000 litres.

The flow:
- filter is gravity fed from the pond via 2 (4 inch) bottom drains
- filter size = 5 ft wide x 14ft long x 2ft deep (water depth = 1.5 ft), split into 4 bays of 5ft wide x 3 ft long.
- water from the pond passes into the first filter bay; this is 1/3rd filled with brushes - so water passes through a settlement area, then through the bushes. I find lots of sediment/leaves etc settle in this bay. Water then passes into bay two
- filter bay 2 has flocor; water passes into bay 3
- filter bay 3 has gravel; water passes into bay 4
- filter bay 4 has volcanic rock. The pump is sited in filter bay 4 after the rock.
- the pump is an aquamax 16000. Water is pumped through a 55w uv, through a 6kw titanium electo heater and directed back into the pond
- there is a header pond which I’ve bypassed for the winter. In the summer, the water would be pumped into the header pond, which is about 2 ft higher than the pond. The header pond dimensions are - c. 1m x 1m x 1.5 ft; from the header pond, water flows into the pond over a waterfall.


Reasons for changing the filter

- I want to reduce my weekly cleaning time. I have about 1 to 1.5 hrs of cleaning to do each week which involves vacuuming the pond, settlement area in filter bay 1 and some brushes.
- The media is going to be a real pain to clean and keep clean based on my experience of cleaning out the filter this summer. Also, I have no way of removing nitrate, except for water changes which I feel is imperfect.

I would like to have:
- An easy to clean filter, which means I can reduce my weekly maintenance time and have a cleaner system.
- I would like to build as much of my system as possible myself, for two reasons. A) for a sense of satisfaction, b) to keep the costs down.
- I would like to keep water such that my koi can grow well. I would like my koi to achieve their potential, and I realise this means different things to different people. The fish I’ve bought will have their limitations no doubt, but nevertheless, I’d like them to grow as large as possible, have good skin. I don’t plan to show fish, although that might change. I would like to keep show quality fish during my time in the hobby, and keep my current koi in a manner that would befit a show quality fish.


Other points:

I have constraints about the amount of money I’m willing to put into doing this, so for example I want to keep the running costs down, I don’t want to heat the pond to high temperatures and I don’t want to spend thousands on a filter system. I guess I’m looking to get most bang for my buck.

We’ve thought about covering the pond, and will probably do it. I’m a bit conflicted because I like seeing the koi from the upstairs windows in our house.

I live in a locality that’s always around 2 degrees cooler than a few miles away. In the recent cold spell my pond froze over except for the stream area. I have a heater and am currently using it stop the temperature dropping below 5 degrees. Even with the heater, I recorded a minimum water temperature of 2.5 degrees on a portable thermometer over the recent cold spell. The portable thermometer reads around 1 degree lower than the electro heater temp reading.



For the filter - I am considering the following options:

a) Coverting bay 1 into a diy easy for mechanical filtration, then for biological filtration, replacing bay 2-4 with bioceonesis baskets and emplying anoxic filtration as described in the recent koi carp magazine article

b) Removing all the current media. Then converting bay 1 into a diy easy for mechanical filtration. Using bay 2 with K1 media and air for biological filtration.

Sub option - disconnect bay 3 and 4 from the filter, and use them for decorative garden planting.
Sub option - use bay 3 and 4 as vegetation filters. I ‘m considering growing watercress. I like the idea that plants could remove lots of pollutants from the pond.

c) leaving bay 1 as it stands to maintain a mechanical filter for larger particles and leaves etc. Putting a pump in bay 2 and pumping to a diy easy in a barrel, then to another barrel with K1 and air for biological filtration.

There is no skimmer. Clearly not ideal, and I’m constantly skimming the surface with a net; this takes up a lot of time, and something that should be changed. I am considering the following options: 1) leave it as it is, 2) add a stand along pump/skimmer like the oase one 3)in a future development, I might raise the sides of the pond by 2 feet and include one or two skimmers in the wall. 4)add a skimmer at the current water level, although I imagine this would be a bit of a pain. Thoughts please..

plan of the filter

filter.jpg (57.27 KiB) Viewed 16100 times

plan of the pond

pond.jpg (37.51 KiB) Viewed 16099 times

View of the pond from upstairs

overhead picture of the pond.jpg (22.1 KiB) Viewed 16096 times

koi - no flash

all 5 koi - no flash.JPG (62.63 KiB) Viewed 16096 times

koi with flash

all 5 koi, with flash.JPG (43.04 KiB) Viewed 16092 times

[tlux]

hi. i am suprised no one has replied to your post. i have read up on anoxic filtration and found it verry interesting especialy the low maintainance and low costs involved. if i had the space i would definitly try it.from looking at your setup you have the ideal oppotunity to try it.on raising the height and adding a skimmer that would be a good idea as the koi will benefit from the extra depth.why not plant up the stream with cress etc.? good luck with your project and lets know how you get on.reguards tommy.

[eds]

Sorry no-one replied to this - I guess it must have been the timing over Christmas maybe?

I know nothing about the anoxic filtration other than what I've read so can't really recommend that, but if you try it let us know how you get on.

Personally I'd use static and fluidised K1 in your current filter. You know the layout better than I can see from the diagrams but I'd have static K1 in either the first or second chamber (if in the second then using the first empty, as pure settlement) and then two or three chambers of fluidised K1.

To speed up cleaning, any chambers that will not be aerated constantly really need benched bases so that most of the debris will drain away under gravity which will reduce the time to clean.

As to the skimmer, if you can dig away at the side of the pond somewhere you could fit a skimmer into the wall and then either gravity feed it to another filter or pump feed it to one such as a shower.

[ajb]

Thanks for your responses; it does feel better having had a couple of responses now.

For the skimmer - I was thinking of doing what you suggest. Would you add a skimmer with it's own basket or have a skimmer without a basket flowing say to a vortex which might have a larger holding capacity? Can you suggest a good skimmer?

For the static KI - the filter bay's are quite low height - roughly 18 inches of water height. What thickness of static K1 would I need the incoming water to flow through before exiting the bay? I guess there's another related question - for diy static K1 - what shape of static K1 is optimal, e.g. a 10 cm deep layer spread out over a 900cm2 area, or a 30cm deep layer spread out over a 300cm2 area?

Adam.

[eds]

For the skimmer - I was thinking of doing what you suggest. Would you add a skimmer with it's own basket or have a skimmer without a basket flowing say to a vortex which might have a larger holding capacity? Can you suggest a good skimmer?

I've got one of the wide-mouth black skimmers from here, http://www.coastal-koi.com/shopping.php?class_id=81, wih the skimmer guard too to stop fish going in! I'm currently running it just with the basket in before the pump but I'm getting tired of cleaning the basket out. If I had the space I'd run it into a seive. I'd do this over a vortex if you can as the seive will strain out the floating and heavier than water particles. Another option would be static K1 in the vortex.

For the static KI - the filter bay's are quite low height - roughly 18 inches of water height. What thickness of static K1 would I need the incoming water to flow through before exiting the bay? I guess there's another related question - for diy static K1 - what shape of static K1 is optimal, e.g. a 10 cm deep layer spread out over a 900cm2 area, or a 30cm deep layer spread out over a 300cm2 area?

IME you only need enough K1 so that when the air is turned off it covers the outlet screen and a little more. I've got about 6" in mine and the otulet is about 3-4" deep depending on the water level. The K1 tends to bunch around the outlet and the dirt collects there. A long shallow area of K1 will only collect waste around the outlet. If you put too much in though then it won't mix well when you're cleaning it - make sure you have less than 50% of the container's volume in K1.

How are you planning to do the outlets to the next chamber?

[ajb]

Thanks for the tips.

Re: flow into the next bay - at the moment there are 2x 4 inch pipes standing vertically in each bay that skim the water from that bay and take it into the next bay. THey are open topped 4 inch pipes. To make them K1 proof, I was planning on lowering the skim height to create about 2 to 3 inches head, and covering them with a fine mesh filter cage - or putting a plug in the top of the 4 inch pipes and drilling lots of small holes in it and creating water flow gaps in the 4 inch pipes with an angle grinder or something similar.

[eds]

I'd bring the pipes up to above the water level and then cut slots in the sides of the pipe. I use a circular saw on mine and it makes 4mm slots that are perfect IME.

Here's a photo of them in the divider in my filter,


This is how I set up a pump fed static K1 filter on my QT system before changing it to a shower. It gave crystal clear water. The slots around the top worked well and it never overflowed.

[ajb]

Thanks Ed, the pics are really helpful.

I plan to make the adjustments to my filter bays so I have a static K1 followed by moving K1 - and will take before and after shots so you can how I've got on.

I just looked at the cost of air pumps and was a little shocked - the cost of the moving K1 section is going to be quite pricey; there's the cost of K1 then the cost of the air pump. I've read that the Nexus 310 can use up to 300l K1 for bio filtration and that would cover a pond of 7500gallons - my pond is c.4500 gallons and I'll aim for 300l K1 to make sure I'm over bio filtering.

Do you know what size of air pump do I would need for different volums of moving K1? e.g. what size air pump for 100l, 200l, or 300l K1?

To get the air into the bays, I was thinking of running air hose along the base of the bays held down with some clips - then making small holes in the air holes for outlets. Is this how you would do it or is there another way? How big should the holes in the air hose be?

Adam.

[eds]

I just looked at the cost of air pumps and was a little shocked - the cost of the moving K1 section is going to be quite pricey; there's the cost of K1 then the cost of the air pump. I've read that the Nexus 310 can use up to 300l K1 for bio filtration and that would cover a pond of 7500gallons - my pond is c.4500 gallons and I'll aim for 300l K1 to make sure I'm over bio filtering.

Do you know what size of air pump do I would need for different volums of moving K1? e.g. what size air pump for 100l, 200l, or 300l K1?

Ebay is your friend Adam! I've got a 100l Hi Blo air pump bought from Ebay and it's great. I found I needed lots of air in my fluidised chamber as it's long and thin with a high flow rate. If yours is larger and less velocity you will probably need less air. Hopefully some more folk will chip in with how much air they use.

Just looking, they've gone up a bit since I bought mine, but here's one, http://cgi.ebay.co.uk/ET120-Air-Pump-Ko ... 1c0debbe0e" onclick="window.open(this.href);return false;

Or a 60 litre one at half the price, http://cgi.ebay.co.uk/60-LT-MIN-AIR-PUM ... 5ad6e44290" onclick="window.open(this.href);return false;