As we near the end of this chapter in The Bristol Fish Projects life Its with great sadness that I have to report a catastrophe & at the same time announce a great joy.
I have managed to kill 40 out of 45 of our Tilapia fish in one go, but all is not lost as the day before I discovered 100’s of baby Tilapia fry!
As some of you may know we were looking at culling the fish in the next weeks for our feast in Victoria Park, Bristol on the 18th August. At this point there are 3 things that may have caused it (or a combination of all 3?) Before I start to tell you what happened I should start at the beginning of my problems.
Having been heavily infested with Aphids (green Fly) then followed by Whitefly in the grow tent, which is a perfect incubation environment for these types of creepy crawlies I had tried several different applications of pest control. From home made Garlic & washing up liquid sprays to pressure hosing the blighters off manually. Then we added 500 predators to the grow space (Aphidius Colemanii ) a parasitic wasp that lays its eggs inside the Aphids body using the pest as an artificial womb, but a combination of a co worker knocking a segment of the 15 minute timer controlling the lights to the off position accidentally & another leaving the tent open at just the right time saw them fly off towards the outdoor light.
Then I found a good product called Bio Defence from Atami the plants perked up & the numbers of pests went down but as this product is more about prevention rather than cure the numbers of pest started to increase again. So I decided to take some drastic action & introduce a “Pest Off” Pemethrine 13.25% smoke fumer to the Grow Tent. I know this product is very toxic to the aquatic environment so I removed the 45 fish into a 200 Ltr holding tank. The young fry were put into a bucket next to the 200L tank & I emptied the water from the system & let a smoke bomb off in the tent.
When I returned the next morning I was surprised to find one of the larger fish flapping around on the floor of the shop. It had jumped out but there were not any sign’s of water on the floor, so how long it had been there I’m not sure? So I picked it up put it back into the 200L tank (placing a lid on it this time) & it swam off. Anyways I was busy in the shop & didn’t really manage to address the fish again that day except for the fact that I had spotted more pests in the substrate/clay balls that we grow our plants in & thought I would repeat the operation with the smoke bomb again. This time I thought I would add a large oscillating fan blowing over the top of the 200L tank to stop any smoke (if escaped from the tent) settling on the water! Here’s were I made a mistake by placing the fan onto the airline & stopping the airflow. Would that have killed them in one night? after all they are known for being a hardy drought fish. I have also heard that when in captivity its possible that when 1 fish dies it puts off a hormone that can kill all the other fish ? So I arrived at work the next day & the 1 fish (I think it was the same one) that I found on the floor was floating on top of the water dead. OK I thought & got my net to check the others out & to my horror all except 5 of the smaller ones had also gone.
So here are the 3 things that I believe did it.
1, The Permethrin
2, The Air line
3, Death Hormone
4, All of the above
Still what is baffling is the survival of the smaller fish?
Right now I’m not sure about using the same pebbles again in the set up because of the Pemethrin lingering? I have added a 2L of of Maxi crop suggested by Murry Hallam to the fresh water to cycle it again within 2 weeks (I know we may have had enough bacteria on the pebbles anyways) but I thought we would be able to grow plants straight away (it smells pleasant at first & now it smells unpleasant & will attract more fly’s & pests I’m sure) but it will give me a couple of weeks to decide what to do & what to stock, possibly Koi? because they look nice in the shop & they might be more of a money crop in the longer run.
Im sincerely sorry for what I have done but feel that one door is closing & another is now opening on The BFP so, please let me know your thoughts? You can use the form below to contact me or I can discuss what happened at the fish feast on the 18th.