Disaster??

The second system, the big black one, suffered a major attack of a pest shown at various stages in the first 3 pictures. It is a little green grub, max size about 8 -10 mm long. Pupates ala the white cocoon and then hatches into a small moth which is also about 8mm long- rather boring appearence grey/brown colouration.

I have killed all the moths so can't take a pic for this post.
If I tried I could find a lot of the grubs and pick them off and then feed them to the fish. However I was not winning.

In a desperate effort to get this problem under control I decided to make some rhubarb leaf spray. A web search provided a number of different ways to make rhubarb spray . There was significant variation in the methods . However I made some but in my enthusiasm I have almost certainly killed off the bio filter in the grow bed. I did manage to kill most of the grubs and the moths but not before creating a new problem. You can see the current state of the growbed in this picture. A series of water tests have shown consistantly high ammonia readings which are bad news for the fish. We have been doing big (30-50%) water changes a couple of times a week recently. Might add the water is not wasted- it goes onto Di's pot plants which seem to be thriving on it.

It's not all bad news. The new GBs are doing well as shown by the last pictures. These were supplied with water from the main fish tank and are topped up daily with 5 or 10 litres of fishy water to ensure a supply of nutrients for the veggies. I have recently moved half a dozen or so of the Silver perch from the black fish tank into one of these new 250 litre tanks- they hide all the time and don't feed anywhere nearly as enthusiastically as the fish in the main tank.
The main plants in the new GBs are Vietnamese mint and a Habenaro Chilli as mentioned before. These are really too hot to eat for us but we have some slightly crazy friends who accept what we unload onto them when they see the plant.
As before the seeds for these new plantings were simply placed straight into the gravel. We only use seedlings when Di sees something she really wants in one of the many trips to the local nurseries. The habenaro chill was one such seedling as our attempts to grow plants from last years chillies were not successful.