HDH wrote:

Hi All,
This pic of my moderately planted 55
(http://www.straightlinetech.com/tank30-mar-03.jpg) shows fairly well the
problem I'm having with cloudy water. Quick-specs:

My Aquarium Experience: 6 months
55 gallon, established 3 months, fishless-cycled
Ammonia, Nitrites, Nitrates: all zero
Ph: 7.6
Temp: 77
Water changes: 25% every two weeks.
Filtrations: Emperor 400

Lighting: twin-tube flourescent (80w) 12 hrs/day

Am I right that the cloudiness is likely from the driftwood tannins? I
really like these two pieces of wood and want to leave them in. I find that
using charcoal (comes in the standard Emperor filters) helps a little with
the cloudiness, but I also recall that charcoal removes certain trace
elements that the plants need.

Howard,

It's tough to tell from the photo, but that looks like an algae bloom (green
water) rather than a bacterial bloom, which tends to look like you poured milk
in the tank. Tanin staining is yellowish but crystal clear, and the photo shows
cloudyness.

Read all about it here (Be sure to read the WHOLE page-real causes aren't
discussed initially).
http://www.thekrib.com/Plants/Algae/green-water.html

Bottom line: you can spend a lot of money on diatom filters and UV sterilizers,
or you can change your water a bit more often and keep an eye on nutrient
levels. Both work.

Charcoal definitely clears tanin staining from water. But it won't help this
issue.