With the start of a new week and we have enough gravel made to replace the second systems grow bed. Now we can start to clean out the old gravel that had lime stone and coral in it.
This system has a seperate bio-filter that will keep the benificial bacteria living while the new gravel has time grow it’s own.
We placed the plants already living in the system into a tub with water and an air pump in it to keep oxygen in the water while the gravel is changed out.
As I have found with most systems, the first time you clean out the gravel you will find out just how important the first gravel wash is and just how much more washing could have been done the first time.
Having changed the gravel out, it is time to replant and plumb the system to incorperate the float beds as it will be a hybrid style, with one flood and drain gravel bed and two raft beds.
Taps are added to the lines going to both the flood and drain and raft beds to allow adjustments to the flow of water. Not enough flow to the flood and drain bed will stop the bell syphon from working, but we still need enough going to the raft beds to keep good water movement and reduce dead spots of water. I am also on the look out for a one way flow valve for the raft bed water line in case of a power out, so water doesn’t drain back down the line and empty the grow beds.
We did some plumbing to create water flow into both gravel and raft grow beds. To do this, we used 6x20x20inch (15x50x50cm) poly board cut down to make four 1inch rafts for each bed. Cutting four pieces of 1inch timbers and using a long fine tooth saw to cut evenly through the poly board.
With a trip to the farm to collect some timber for the up coming green house to cover the systems, I also picked up some strewberry plants and a sage plant to take some cutting from. The strawberries will go into the raft system while cuttings from the sage and basil plants will go into the gravel. I also got some cuttings from a grape vine that seem to do well both in the tropics and at sea level to put into system to see if they will take root. The plants have been in the system for 5 days now with just one leaf left on the cutting and they look to be doing well with no wilting as yet.
As talked about before, we have to work with what we can get locally, it may not be perfect but that is the chalange of the DR and other place you may incounter similar problems with the lack of the right material.
Do what works for you and the area your working in, comprimise where you need to, and solve each problem one step at a time. Build a system that works for you, your climate and the equipment avalable at hand.
As the work continues with the ever present, always happy Sammy the dog supervising.