Autumn leaves to aqua? Contamination or something positive?

[Helina]

Hey!

I know there are some special leaves sold for aqua, but does a regular tree leaf do too or may it cause some contamination?

Might it be decorative, and eventually extra nutrition for Neocaridina shrimp and algae eaters?
Or a contamination risk?

EDIT: I removed the maple leaf for now, just to be sure.

 

[GaryE]

I planted a red oak specifically to harvest leaves (and enjoy the tree). I've used oak leaves for decades.

Maples decompose very quickly underwater. They're excellent for tannins, but messy. Red oak (Q. rubra) or burr oak (Q macrocarpa) last much longer if you pick them from the tree when they are brown. If you harvest them from the ground, especially after a rain or two, they aren't great. I picked some early last evening because we were expecting a wind storm today. Last year, I waited too long and a storm stripped the tree.

I'm drying them on a table, and in a couple of weeks, will use them to release tannins (a lot of tannins) into my rainforest fish tanks. My tree is young and only 3m high, so every year, I should have more leaves.

Both oaks are native here, but have been almost eliminated by forestry practices favouring pines. So I also get to reintroduce a once common tree.

 

[Colin_T]

Any deciduous tree is normally fine to use. Just let the leaves drop and collect them up. As long as they don't have bird poop or any chemicals on them, they are fine.

Don't use leaves from conifers or plants that produce a white sap when leaves or branches are broken off them.

 

[GaryE]

Any deciduous tree is normally fine to use. Just let the leaves drop and collect them up. As long as they don't have bird poop or any chemicals on them, they are fine.

Don't use leaves from conifers or plants that produce a white sap when leaves or branches are broken off them.

I don't know Australian deciduous trees. I'll respectfully disagree with Colin about the trees we'd find in Canada or Finland, as they can vary in usefulness. None will harm our aquatic creatures, but they vary radically in durability and tannin release. To pick them after they fall can have issues, since Finns have the same autumn rains we do. Right now, we can all get ready for snow together. Really wet leaves can be used immediately, but you want leaves that can dry out for use across an entire winter. Get them off the tree and air dry them. It's worth it.

The need for good tannins never sleeps!

I've tried birch, mountain ash, maples, elm and various oaks. Maples create outstanding photo backgrounds as they decompose quickly (producing powder) but their fibres hold together in rich patterns. If you want to make a tea outside the tank, they are tannin rich. But the oak family is what you want if the tank is to get the full benefits.

There's a market in imported tropical tree leaves, but it seems silly to buy most if you have equally good resources all around you. The only one I'd consider is Catappa, Indian Almond leaves, for their antiseptic properties.

 

[WhistlingBadger]

I’ve heard walnut leaves can be toxic, as can leaves of the cherry family. But most deciduous leaves will work fine. Durability will vary though.

 

[GaryE]

I’ve heard walnut leaves can be toxic, as can leaves of the cherry family. But most deciduous leaves will work fine. Durability will vary though.

Hmm. We don't have walnut trees here, except as a very rare ornamental. Cherries are also less common and their leaves have never caught my eye. I'll avoid them. Thanks.

 

[Helina]

Wow! So many interesting answers! Brilliant, thank you all! I guess I might try it out after all.
Would you add freshly dropped leaves or always wait for them to be completely dried up? From fresh leaves, wonder if there's a danger of any infectious leaf diseases able to carry on living in the aqua on other plants? Or other such contamination?

 

[GaryE]

I think wet leaves will decompose more rapidly, and become soft. I've always used dried leaves, because they stay together for longer.

I don't think there is any risk of contamination, but more of a risk of mold or fungus on them. It's ugly, but I doubt it's especially harmful except to water quality.