Is 30ml great for a starting batch or would I need more?
Edexcel exam board Algal Balls
- Thread starter Peter Sigsworth
- Start date
Peter Sigsworth
COMMITTEE
Yes, as you will culture it up - tip into a large container with water either rain/distilled/deionised or tap safe water add a few drops of baby bio/ferilizer and then aerate constantly on window sill for a couple of weeks
Go to the start of this thread and read through the tips
I started my second attempt at culturing algae a couple of weeks ago but I've hit a problem. The first two weeks it was going really well and the solution was starting to become a darker green but this week it seems to have just started separating and sticking to the sides. Over the weekend it had completely separated (like it was just clear liquid with algae just sitting at the bottom of the flask). I've shaken it and turned the air pump up to max but it seems to still be settling/sticking to the sides. I'm not sure what I've done wrong 
Peter Sigsworth
COMMITTEE
You do get that - just keep trying to break it up - I use the aerator by moving the stone (on full bubbling) across the sides to dislodge - it should recover if you regularly keep doing thisI started my second attempt at culturing algae a couple of weeks ago but I've hit a problem. The first two weeks it was going really well and the solution was starting to become a darker green but this week it seems to have just started separating and sticking to the sides. Over the weekend it had completely separated (like it was just clear liquid with algae just sitting at the bottom of the flask). I've shaken it and turned the air pump up to max but it seems to still be settling/sticking to the sides. I'm not sure what I've done wrong
This happened to me, the way I fixed it was by replacing the air stone (although you could try cleaning it)I started my second attempt at culturing algae a couple of weeks ago but I've hit a problem. The first two weeks it was going really well and the solution was starting to become a darker green but this week it seems to have just started separating and sticking to the sides. Over the weekend it had completely separated (like it was just clear liquid with algae just sitting at the bottom of the flask). I've shaken it and turned the air pump up to max but it seems to still be settling/sticking to the sides. I'm not sure what I've done wrong
Peter Sigsworth
COMMITTEE
Good call - it is common for this to happen or even not have a powerful enough pump - the bigger and deeper the vessel the stronger the pump required. With 5L demijohn, I use a Tetra APS 400
I'll try cleaning the air stone because it does seem to be worse in one of the flasks. I do have the same pump as you and the volume of my culture is around 1.5L at the moment (split across two conical flasks). The first time I tried to culture I put the 30ml starter straight into 5L but it just never seemed to go any greener so this time I've put the starter into a smaller volume to try and make myself 200ml of concentrate that I can then put into 5L like you said you do when sub-culturing.
Peter Sigsworth
COMMITTEE
Good luck....
Ooh matching cupboard doors
Peter Sigsworth
COMMITTEE
Yes, you need a much larger volume because you have to concentrate the culture up 5l demijohn
after about 2-3 weeks
Let it settle for a day or so
discard the clear top solution then make balls from bottom dark green 'algal soup'
@Peter Sigsworth the algae that you sent me last year went nice and opaque, but never went deep green - apart from the first couple of weeks when it was quite bright green it's always been shades of yellow-green. A couple of times when it started to look decidedly unwell I tipped out all but about 2 inches depth and topped back up with distilled water and a couple of drops of baby bio, but the same thing just happens again I put a lamp on it about a fortnight ago, which doesn't seem to be making any difference so far. Any other tips ?!
I put a lamp on it about a fortnight ago, which doesn't seem to be making any difference so far. Any other tips ?!
Peter Sigsworth
COMMITTEE
I can only think it's light and time of year - It should improve as the day length increases - mine is kept on a west facing window sill.
Hi @Peter Sigsworth, those this offer still stand? Our Algae that has been growing like a trooper for years is suddenly starting to die on us.
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Peter Sigsworth
COMMITTEE
Unfortunately I no longer work there and my replacement has chucked it all away
Hi all - today is the day I am going to trial the Algal balls practical. I have a lovely "pea soup green" culture of algae. What's the best way to keep back a subculture for next academic year? We bought a starter culture last year and didn't end up trialling it so it sat on the shelf over the summer hols and survived until I started the culture about 6 weeks ago. I have looked at them under the microscope and seem to have a pure culture of the Scenedesmus quadricauda so keen to save some back and save us having to purchase again.