A few general questions...

[Starburster]

Hey guys,
A couple of things I've noticed since we just harvested our first few lettuces. We've been growing cos lettuce and while they're big, they're not completely full... that is, they didn't quite develop a heavy heart. Is this common or does anyone have any ideas as to why this might have happened? They taste fine.
Also... we got some new food from Murray on Monday for the barra and they don't like it. When we throw it in, they all come to the surface, have a look at it and then drop down to the bottom. Maybe they don't like the taste? They ate it the first day. We did a fairly big water change yesterday because our nitrites and nitrates were a little high so maybe that's shocked them a little and put them off their food. The tank is stable at around 26 degrees.
Anyone ever encounter this before?
Any suggestions would be wonderful...
Cheers,
B

[Murray]

I have noticed this about the cos lettuce as well. For our own use it does not bother us at all. We just take the leaves off the outside and the plant continues to grow.
I think it might also be a sunlight thing as well. Lettuce like plenty of sun.
You would not get a lot of winter sun into that greenhouse of yours, would you ?
My fish are eating that new batch of food but not with much enthusiasm.
I am getting in a different batch of Barra food in the next couple of days , I will send some over to you.
Muzza

[Starburster]

The issue with the cos is not a huge one, it was just something we noticed. We don't get a huge amount of sun in the greenhouse in the winter, but it's been enough to stimulate some fairly rapid growth in most of the plants. It was pretty much the sunniest place we could get in the school without erecting a new greenhouse or taking someone else's space. In the summer, we get plenty of sun, although unfortunately we won't grow plants during the peak of the season. Ah well.
I'm glad it's not just us with the food then... I thought maybe we'd done something terrible to the fish. What was the first type of food that you sent us? I know it was 4mm floating pellets but that's about it.
Thanks,
B

[Aquatic Oasis]

Hello peoples,
In my experience in Hydroponics we have noted that heart style lettuce are generally a little harder to grow than the fancy leaf varieties. In my experience this may be caused by insufficient light but more likely from a lack of calcium. Maybe try a foliar application of calcium nitrate. Calicium is generally better asorbed thru foliar applications than thru root supply.