If using aged water (AW) did reduce the amount of cyanobacteria in my aquarium, if it is really was the factor responsible for the reduction I observed in Chapter XI, then I would expect it to do so reproducibly and over a similar amount of time. In Chapter XI I noted that I observed a dramatic reduction within five weeks, so for me to be convinced this time I would have to see a dramatic reduction over a similar timescale.
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| Week 148. Cyanobacteria (possibly green Lyngbya mats and brown unicellular cyanobacteria mats) from a freshwater aquarium. Photo taken Immediately before the first AW change. |
As you can see, by week 148 species 2 was growing well on the Moss Ball and Amazon Sword but also on the tank walls, bog wood and gravel (the gravel was more affected at the far end of the tank). As I mentioned in Chapter 19, I was pretty efficient at removing it from the plants at this point and ruthlessly efficient at removing it from the tank walls and gravel, so most of what you see here will have grown in the week since the last water change.
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| Week 154. Immediately before the seventh AW change. |
I could argue that there was less cyanobacteria in the tank at this point but I can't claim that the reduction had been dramatic. The bogwood was still almost covered and the Moss Ball. There was still cyanobacteria on the gravel and tank walls.
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| Week 154. |
I think the best I can say is that the cyanobacteria problem hadn't got any worse, which is something because in my experience cyanobacteria problems always get worse. But there was little evidence that using AW is worthwhile. It occurred to me that one reason why it had failed might be the condition of the container I age my tap water in.
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| Week 149. |
The inside had become almost entirely coated in a slimy layer of what I assume to be bacteria. So in an attempt to replicate the conditions when I first used AW and the container was new, I gave it a really good clean with a bottle brush and continued the weekly AW changes.
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| Week 160. |
I think it's fair to say that over the next six weeks there has been a dramatic reduction in the amount of species 2. There is still some on the bogwood and gravel, but the plants are mainly clear, and there is none on the tank walls. Interestingly, the colonial unicellular cyanobacteria has returned on the Amazon Sword leaves. It's like the cyanobacteria succession I saw in Chapter 19 is happening in reverse. If that is true then over the next few weeks I should see a reduction in the brown unicellular mats. At that point I will switch back to fresh tap water in the expectation of seeing the succession played out once more.
