Are you adding CO2 to your planted tank? Are dosing fertizliers at all?
I'm not sure what might be causing your green water only during these
winter months, but typically plants can "out-compete" algae for
nutrients provided all the necessary nutrients are at suitable levels.
Any one that is too low will prevent your plants from being able to
maximize utlization of the others. The three big things to consider are
1.) Light (if you are using flourescent bulbs, make sure to change them
once a year or so), 2.) CO2 - fish do not really provide enough on
their own so it's usually a good idea to supplement this vital nutrient
either through CO2 injection or with something like Flourish Excel (a
liquid Carbon product). 3.) Iron and other minerals either in
specialized soil (I use Eco-Complete) or through liquid dosing. Patrick
Timlin who is on this group is an expert on planted tanks and I've
gotten a lot of good advice from his posts in the past.
You can always try the blackout method for getting rid of the green
water or a flocculant which will bind the algae particles into larger
clumps so they can be removed by your filter, but these will not remove
the root cause of the problem.
Best of luck,
--- In email@example.com, "Kelly" <krg22@...> wrote:
> I have a 46g fresh water tank. Every year around december/january the
> water turns this murky green. We do regular changes of 15g at least
> every other week, but we try to do it weekly. Last year we added live
> plants and it seemed to clear it up pretty quickly. This year
> however, we still have those same live plants, so shouldn't they be
> working for me? Any ideas? Should I try new plants or is there
> something else that I need to add to the water?
> Right now we don't have many fish we were thinking of transferring
> them to a smaller tank just until the water cleared up, but that might
> be more stressful then the water they're already used to.
> What do you think?