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Once the cover was on I fitting a pair of water proof fluorescent lights, this enabled me to work a couple of hours every night after work. Rock removal carried on in earnest, some areas were fairly easy to breakup, others were much harder, I found that on a weekend if I shifted 25 plus wheelbarrow loads I had done quite well! Slowly I was getting deeper in the pond and the rock pile on the back drive was getting large again so things were definitely moving along.

It must be mentioned that this pond is built in a totally unorthodox way. This is because of the rock foundation, it will not have a base cast as in most pond constructions. All of the pipework will be laid in channels cut into the rock, these will be back filled with concrete, then the base will have a light screed before the GRP is applied. Same goes for the sides, the rock will be rendered and then Glass Fibre applied. The only blockwork will be above rock level with the exception of the entrance to the filter area which will be made from 4" concrete blocks laid on their sides.

By February 2003 the majority of rock had been removed and the slots in the floor had been cut for the 4 bottom drains. Also I had removed the block-work from the back of the pond and cut the dog-leg  out making the back of the pond straight. A footing was then laid and two course's  of blocks laid on top of this. Half a block was left out for later fitting of a Certikin Pool Skimmer.

The timber batten was fitted with 12mm ply packers to aid positioning. The packers allowed the skimmer to protrude beyond the blockwork. Later when the render is applied it would leave the skimmer flush.

Below the skimmer a tunnel was carved out for the return feed from the skimmer filtration and a 4" pipe was cast in.          

The skimmer will be powered by an Aquamax 15,000. It will pump to an above ground filter system consisting of a Mini Vortex 24" diameter containing a 410 Answer, then onto two 48" diameter Bio Vortex's. The first Bio chamber will contain 300ltr of K1 Kaldness, the second Japanese Matting. This filter system will also be connected to the 2,500 gallon pond in my fish house. This filter will be switchable, so that it can run on one pond or the other, or both. This will enable me to bring the koi inside for the winter if heating the main pond proves to expensive. While running on the main pond the water will return by gravity through the 4" pipe. 

With the skimmer and return pipe fitted it was time to return to pipes on the bottom of the pond. The first bottom drain was set on a pile of concrete at 6' depth and leveled. Then using this as a datum point the others were set on their own concrete.

A former was then cut from plywood to slot the pipework through, this held all the pipes level and would form the foundation for the dividing wall between filter area and pond.

The pipes connecting the drains were slowly added along with the air feed pipes, holes were cut in the ply former to accommodate all the pipes coming through to the filter area.

The next step for the bottom of the pond is to back fill the bottom drains and associated pipe work, this will be just enough concrete to cover the pipes, leaving the final fill of the drain line slots until the whole base is rendered.

The original plan was to follow modern convention and use TPR returns in 4 locations around the pond. The slots for these were cut into the base at the earlier time when the Bottom drain slots were cut. Since I have had a rethink and have consulted with a design engineer. The concept of TPR's is to create a circular motion in the water and to wash the bottom of the pond, adding waste removal to the bottom drains. Looking at the size of the pond and realising the amount of pipe it would involve, I started wondering how much pumping power I would lose with all this pipe work creating head pressure. So we discussed the merits and pitfalls of fitting all 4 returns horizontally in one place close to the filter area, these would be fitted one on top of each other at 5" centers. The view was that we would get the same circular movement and similar wash, perhaps tailing off towards the end of the circuit. But the pumps would be returning more water and this would be a benefit and save wasted power.  We decided that the pull from the Spindrifter air domes would be quite considerable and these would do a fair job of pulling waste to the drains. Time will tell, it's a gamble I am prepared to take, all pipe and elbows for this had been previously bought so it was not a cost decision but pure mechanics.

I have started putting the first coat of render on the walls. First they are made as smooth (joke) as possible with the kango and then a mix of 3 parts stone dust, 3 parts pit sand and 1 part cement is applied. Previously I have been filling the deep holes with a little mix.

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