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Re: dramatic increase in light

Teresa wrote:

> Hello, I am thinking of upgrading the light over one of my tanks.  It is a
> planted 38 gallon tank that has been set up for a year and a half and is
> doing well.  It has 60 watts normal fluorescent plus a little added sunlight
> in summer no Co2 very low maintenance.  Plants grow slowly but well enough
> and there is very little algae.  I want to get a 96 watt custom sealife
> compact fluorescent strip.  My question is, when I increase the light will I
> get the burn on plant leaves that I sometimes get when I move thehouseplants
> on to the deck for the summer?  Is there a way to avoid this?  Are there
> other consequences to increasing light that I am unaware of?

I have the same tank and lighting that you have now.  It even has the
same maintenance regimen.  About 6 or 7 years ago I started using more
intensive methods in my other tanks, but I kept that one tank as it was
to remind myself of where I came from in the hobby.  Now I'm considering

You probably don't need to worry about scorching the plant leaves, but
there will probably be a *lot* of other changes in your tank.  Right now
your tank sounds like it has a reasonable balance between plants, light,
fertilization and maintenance.  The brighter light will throw all of
that out of balance.

Brighter light means more photosynthesis and higher demands for CO2. 
The dissolved CO2 levels will drop and there will be more competition
for the available CO2.  Some of the plants you have now may not be
competitive enough to survive that change.  Some algae may be more

More photosynthesis generally means more growth, and that means bigger
demands for nitrogen, phosphorus, iron and all the other essential
nutrients.  You will need to provide for the plants' increased demands. 
If you don't then after some initial healthy growth you may see the
onset of deficiency symptoms and your tank may develop some annoying new
algae problems.

And of course, all that new growth means more maintenance, especially
pruning and replanting.  If your interests are like mine then that
pruning and replanting is actually one of the fun parts of the hobby, so
that isn't a bad thing.

Your fish may not care much for the change.  You probably don't have to
worry much with a tank that's been up for a year and a half, because
your fish would be mostly young.  One of my concerns when I upgrade my
tank is that it has been set up for more than 13 years, and there are
some old Botias in the tank that have been there from the beginning and
they are very set in their ways.

You will have several alternatives to rebalance your tank.  You may be
able to simply find a combination of plants that work well with brighter
light and compete evenly for CO2 and nutrients.  In the long run that is
the best way to keep the tank in a low-maintenance state.  It's more
likely that to keep the plants you want that you will need to change a
few other things.  You may need to add CO2 and increase fertilization to
balance the increased light; you may need to add more algivores to help
control algae problems and to do more tank maintenance to keep
appearance up.

So there may be a lot of changes, but if you're really interested in
growing aquatic plants then increasing the light is probably going to
increase your enjoyment of your aquarium.

Roger Miller