totziens

Could it be rotten food or dead fish stuck among your duckweed releasing the smell? I could not smell anything in my tank with duckweed. I could not smell anything in my tank with Salvinia minima either.

Alex123

Here's the pics. I have a jungle look for now but it keeps the algae clear and yes, it's blurry.

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ombcat

This is not uncommon, especially when no fresh air is circulating. I often with all my tanks and windows closed, I will find an order such as this. Goes away when windows are open and fresh air is present.
Better than the smell of cooked fish or cabbage.
Wilma

Alex123

Alright, Wilma, appreciate the support. I am starting to think I am imagining this smell. I would not say it's a better smell than cooked fish. Cooked fish are more intrusive but at least it wets my appetite versus this weedy smell. I didn't know cabbage had any smell.

newbie314

When I open my lids the tank smells like fresh salad that was run through hot water.
At least that would be the best analogy.
I have duckweed and lots of it.

colinsk

I get a smell that bugs me from my aquariums that is vegital. I believe it to be 2,4,6-trichloroanisole (TCA). TCA is an off flavor in beer and wine production and I am pretty sensitive to it. I get it in my tap water for about 3 months a year. Without charcoal filtration I can not drink my tap water during winter. I believe it to come from decaying plant matter. I have decided it is part of the planted tank experience. I don't notice it unless I have the tank open. Once I touch the water I have to wash the sent from my skin.

OldMan

I am no plant expert but have noticed a strong odor from a tank where the surface is covered with frogbit instead of duckweed. It does have an odor suggestive of decaying plant material but the frogbit looks great when I examine it.

Juergen

some fishy smell occurs from my tanks, if I overfeed them...overfeed=more food/organics than the tank ecosystem can handle
and of course, if I stirr up the mud...but this is a different thing
regards