"Chris_S" wrote in message
...
There was no phosphate in the water at all.

Well, there's your problem.

Gee, for years other people told me that the cause of BBA was too much
phosphate. Now you say having no phosphate causes it. This is typical of
the conflicting information I often here about BBA problems.

Obviously you are of the camp that believes you can control BBA with the
water. I bought into that mentality for years, and fought the BBA using
that method. The BBA won. Maybe for some people, their water, their
plants, and their type of BBA, that method can have some success. But it
is
very clear from everything else I have read that more and more 'water
treatment' people are becoming convinced that BBA is a different kind of
problem entirely.

A single thing causing algae is a really bad way to think about it. So is
thinking that you can control it with water conditions. Sure, if you make
the water conditions perfect for the plants, the algae will subside. But
remove the plants, the algae will flourish under the same water parameters.
Again, it helps tremendously to think about the plant health, not the algae.
I know it's not easy because it's counterintuitive, and because we don't
know exactly why it works.

I have seen really nice show aquariums with tons of plant growth and no
BBA.
When I ask the aqua person how they did it, they tell me: "I rinse every
plant in Chlorine before I put it in the tank - I don't let BBA in the
tank". That is how they handle it, they prevent it.

That's because the plant care methodology is a relatively new idea and
because those people probably don't follow the online plant forums very
much. Those folks probably never even heard of adding phosphate.

I've had plant growth through the top of the tank. Swords with 24 inch
leaves, and so much plant growth I had to prune plants every week. Yet
the
BBA never went away. I've read articles from other people who believed
that
water control could combat BBA as well, yet they were left scratching
their
heads when they lost the fight and the BBA kept growing.

That doesn't prove your plants were at the *peak* of their health. When I
say the plants must be as healthy as possible, I don't mean they should
simply be growing "well". I mean, they should be growing as fast as possible
under the available lighting, with every other nutrient being available to
support that growth. In effect, the lighting should be the limiting
nutrient. That means if 30 ppm CO2 is required for that kind of growth, then
25 ppm will not suffice. I don't see any indication that you have seriously
tried to satisfy your plants' every nutrient requirement in this way. It
doesn't matter if your plants appear to grow well. If they can grow better
still with the addition of some nutrient, then they are not growing their
best.

Maybe you can provide some details about tank such the lighting, what kind
of CO2 system, the daily CO2 levels, your dosing regimen and the amount and
type of plants, and we can advise you on what you can do to help the plants.

I do not know if you have any BBA in your tank(s) right now, but if you
would really like to test your theories in practice, I would be happy to
send you some of mine. I can send you a rock or plant with the BBA
species
I have. Just let me know.

Almost every tank has BBA cells in it, including mine. You cannot kill every
last algae cell with nutrient control. That's not the goal. I've had every
kind of algae for the first year of keeping plants (except GW). Believe me,
I was as frustrated as you are. I too was focusing on starving the algae.
All it did was change the predominant type of algae in my tank. Like you,
people were telling me that I should not have even a trace of PO4 in my
tank. I couldn't understand why I couldn't get a reading on my PO4 test, and
yet the algae was choking the plants. But then I started paying attention to
Tom Barr's posts on the APD, where he was suggesting supplementing PO4
instead of depriving your plants of it. That's what did it for me. I was
already adding everything else but PO4, and had a compressed CO2 system.
Since then, I've had minor algae outbreaks here and there. And it turned out
that each time the fix was to *increase* the amount of some nutrient,
whether it was CO2, NO3, or PO4. I keep my CO2 fairly high. But if it slips
for some reason, I get an almost immediate algae outbreak, even if the CO2
is still above 20 ppm. I still have some filamentous algae on the Rotalla
wallichi, which is the hardest plant to grow in my tank. That's why it's
probably the least healthy. I'm sure the solution is in adding the nutrients
more frequently than twice a week, so that the levels never fall very low.

If you send me a plant with algae on it, the algae will disappear through
pruning of old leaves and will not grow on the new ones. If you send me a
rock, it might actually take a long time for the algae to actually die off.
But if I clean off as much of it as possible first, it will not regrow
either.
__
Alex
pcalex (at) hotpop.com