Alas, we lost one the day after we moved the fish into their new home. We had calculated on having 11 fish, this brings us down to 10 fish. I guess losing 1 fish isn’t such a bad thing, after all, we could have lost more. The thing about fish is that they are so sympathetic to their environment that the slightest change in water quality and the fish feel it. I’m hoping that the rest of them survive ok.
And not a day too soon! The nitrifying bacteria has been in the tank for a few days now – so we’ve been waiting for the fish to start the whole system going. Our fish arrived today by courier, in a Styrofoam box, having shipped out 24 hours ago. As we requested from the good folks at livefish.com.au we received 11 silver perch, and they threw in some Thin Val (a type of long growing water plant) and a bit of fish food for free!
Opening up the box they came in tentatively I was very happy to find that the fish were all alive and exceptionally healthy. Can I just say that I’m not really a fish person but these little baby perch, only 40 mm long, are quite personable, exciting little things. They zip around like darts of silver - cool little beasties!
Then we laid the bag, still tied, in our tank. We noticed that the fish had traveled from Bundaberg, famous for its sugar cane and rum production, which is much further north than where we live (and therefore much warmer!). By placing the bag of fish in the tank we allowed the water in the bag to slowly match the tank water temperature.
After a while, we opened the bag and poured in a cup of tank water. We did this every ten or fifteen minutes, acclimating the fish to the water of their soon to be new home. Pretty standard aquarium maintenance stuff.
Meanwhile we created a little house for them to hide in. Joel Malcolm has wide-diameter pipes in his fresh water tanks for his fish to hide in – we used a big unused half pot plant and threaded some Thin Val through its drainage holes.
After about an hour, we released the fish into their new tank. Naturally, they swam straight to the darkest bits and tried to hide from the monsters who were ogling them from above. As evening wore on they seemed to loosen up and they darted up to the surface to check out the new neighborhood. All the environmental features were studied closely by the new fishies – the three streams of water flowing in from the grow bed, the pump, the hose and the new place to hide. Some adventurous fish even tried to nibble random things on the surface. We figured that was a good sign – hungry fish have more on their minds than dying, which is what we really don’t want.
Since the arrival of the fish (all named “Steve” after my eldest brother) we must have looked at them about ten times! Go fishies go!
Remember when you were a kid, waiting for Santa Claus to arrive and deliver presents? Well, we were feeling some of that sort of anticipation this week, waiting for our nitrifying bacteria to arrive in the post. Funnily, I think that at some point the anticipation about receiving presents is replaced with the anticipation of giving presents to the ones you love, so it was with some sort recognition of the child within that I looked each day at our post box for signs of a new parcel. Sure enough, we were soon rewarded with two little bottles, full of bacteria. I can honestly say I never thought I’d be keen to see bacteria in the post box! (It’s definitely better than a huntsman spider in the letter box though, which you usually get round this time of the year.)
That evening we opened up the bottles and applied the bottles to the grow beds. As we have a 500 Litre tank, we put in about 250ml of standard solution in. We don’t yet have any fish, so we could afford to wait for a few days for the solution to circle through the beds and the tank.
This bacteria will break down the ammonia produced by the fish as waste. A special type of bacteria called nitrosomos breaks down ammonia and turns it into nitrites in the grow beds. Another type of bacteria, called nitrobacter breaks down the nitrites and turns it into Nitrates, which the plants use as form of food.
After only a few days, our watercress, which acts as our system barometer telling us if the system is healthy or needs work, was looking lively and well, with many more new green shoots. We took this as a sign that the bacteria had started to produce food for our plants. We’re really looking forward to seeing a bit of a boom in plant growth, which so far has been a bit slow, as we haven’t really had any fish in the system.
… for the bacteria and for the fish to arrive.
I’ve also ordered a new 250 liter grow bed so that we are closer to a 1:1 ratio between water and grow beds. This addition was mostly because I was unsure if we had enough filtering material to clean up the water. It’s true that at the beginning, I shouldn’t worry about that but since adding a new grow bed when you’re seeing trouble doesn’t seem like a good approach. And this way, we have more gravel space to plant more things, closer to areas with more sunlight.
At the moment, our grow beds are in a semi-shaded area, with not much direct sunlight and between that and the fact that we don’t yet have fish in the system, the growth rate we are seeing is pretty poor.
Over the next few days, I will post a few more pictures to my Flickr group on the current state of the system and the strange marks that appeared on the leaves of our lettuces. Maybe someone will be able to help us diagnose what’s happening and give us hints on how to solve it.