Indian Almond Leaves

They don't colour the water badly - well they don't if you only use a bit. I use half a small leaf in my betta's tank as it is supposed to be good for them. The nerites like to nibble on it too. I just put a new half in when the old one starts to fall apart.

Fish from blackwater regions are supposed to like them too.

Thank you both. Richard, are oak leaves as beneficial as Almond?

Many thanks Richard

There's absolutely no "varmint" that could be on leaves or alder cones which will harm fish, shrimps or anything else. Yet another "much ado about nothing" of those scares which seem to permeate fishkeeping.

Alder cones release a lot of tannins into the water, which will colour the water brown. Some fish from soft "brown water" rivers may benefit from these tannins. Unless you have these (some tetras etc) there will be no real benefit in using alder cones.

Oak leaves break down very slowly and any colouration of the water is scarcely noticeable. Whether you boil them or not, colonies of bacteria etc will build up as they leaves slowly break down in the water. These are generally enjoyed by shrimp which will browse on them. Apparently, in many of the waters where shrimp live naturally, there are few or no water plants and the shrimps are always found among dead leaves.

The effect on pH will be negligible unless you stuff the tank full of leaves or cones and don't do any water changes.

I suggest adding a few oak leaves at first and see how things go.

Iv ordered some almond leaves for my planned shrimp tank, after reading this I prob won't buy a 2nd batch

I use Indian Almond Leaves (Cattapa) in the mini-pond and the liquid extract in my aquarium. The leaves and extract are deemed to help fight off infections in both fish and shrimp and also enhance colour.
Beech / Oak leaves stain the water Brown by releasing tannin they also reduce pH to some extent and act as a natural decor for Blackwater species.
Walnut leaves are also used and are deemed to have medicinal properties.

Be careful when adding almond leaves or alder cones. They are relatively very strong and if your water is very soft they can easily cause a pH crash if too many are added. Add them gradually and monitor pH. "Tannins" are tannic acid...

I have very soft water (KH 1, GH 3 naturally) although PH is 7.5ish. The KH and GH figures are elevated to 2.5 and 4.5 respectively with some limestone in the tank. I also have 2 Indian almond leaves in on an almost permanent basis - this has never caused a PH crash/lowering or lowered the KH and GH. I boil the leaves for 5-10 minutes before adding them, to help them to sink. However, there was an incident a few years ago in which I decided that it might be good to add the tannin-stained water to the tank once the boiling water had cooled down - suffice to say it resulted in the fish behaving as though they were drunk / on sedatives - so I wouldn't recommend doing that.

If you boil them first they won't be nearly as strong, as you've boiled a lot of the 'goodness' out of them. I think a whole leaf would probably be ok in 240 litres, but I would still probably add a half at a time. It causes quite a change in the water chemistry as far as the fish are concerned so best to do it gradually I reckon.

I found they took a few days to sink. I just left them floating until they sank.