Why do my old leaves look like this?

[Sacha]

For a while I have had a problem with all the old growth in my tank.

The new growth is always lush and healthy and algae- free. But all the old leaves on all of the plants look like this:







This is a Ludwigia Repens 'Rubin' leaf.

The rest of the stem is perfectly healthy.

At first I thought this was diatoms but now I'm not so sure.

This badly affects Staurogyne Repens, Ludwigia, and also java fern. It looks like some kind of BBA?

The undersides of the leaves are perfectly healthy:



Any advice is very welcome. Thanks.

 

[tim]

Looks like poor flow at the substrate level of the tank is the culprit, a tricky one to solve ime.

 

[dw1305]

Hi all,
It might be BBA,or it might be a green algae, you should be able to tell by the colour, green algae are "grass green", but BBA is a much darker colour. They aren't to every-ones taste but Ramshorn snails will browse all of this type of biofilm off before it becomes visible.

cheers Darrel

 

[Sacha]

Thanks both.

I have quite a lot of MTS but no Ramshorn.

I have recently had to downgrade my pump because the flow was too powerful and the fish were unable to even swim. That's how determined I have been to have good flow. I nearly blew my fish away.

Anyway, the point is, I have very good circulation, low down and everywhere else.

 

[parotet]

Hi Sacha, I got this problem in my previous setup due to two large pieces of redmoor blocking the flow to the bottom leaves of the background plants. I even trimmed down the plants to the substrate to know if this was the problem and yes, it was... once again the plants grew well, free of algae on the top and with some issues on the bottom. I simplified the hardscape and it worked well, much better. Actually I am now enjoying a much more simplified evolution of this setup, free of wood, no hardscape, just plants... Never seen the bottom leaves so beautiful. Not sure what algae it is, ugly stuff anyway.

Jordi

 

[Sacha]

Thanks Jordi,

Interestingly enough I have been considering removing a piece of wood for the tank. I need a bit longer to work out whether it would look good.