When should I prune, and how to identify algae

[Carissa]

Hi,
I have some hygro plants that I've had for a while but I just finally got some better lighting and ferts recently. So now a lot of the lower leaves (older growth) are kind of yellow and have light algae on them and some have holes in the leaves. Would it be good to prune off these leaves and how far should I go with pruning without hurting the plant? Can I prune off 50% of the leaves or will this kill it? I want to encourage new healthy growth. The plants are only about 6" tall or maybe 8" for the bigger one.

Also I have some algae forming on my tank walls and a little just on the edges of the hygro leaves since I increased my lighting. How can I tell the difference between green algae and bga? This algae is green on my tank walls and on the leaves it kind of looks brownish, although it's not brown algae I don't think. How do I know if it's green algae or bga?

Another question I just thought of. When I increased my lighting, both hygro plants sprouted a set of new leaves literally within 24 hours. But after that the growth seemed to slow down a lot. It's like they exhausted something in the water. Any idea what it could be? It's a non co2 tank.

 

[VaughnH]

You probably answered your own question. You don't use CO2, but you increased the lighting on the tank. The more light you have the more important CO2 becomes. And, the more light and CO2 you have, the more important the nitrates, phosphates and traces become.

But, back to the pruning question. hygrophila varieties are stem plants, so you can always prune them by cutting off the top and replanting the top, and/or by leaving the trimmed stubs in the tank to sprout new leaves. It isn't a delicate plant at all, even though a very few of them are not as easy to grow as others are.

 

[Carissa]

I was looking at my hygro plant yesterday and it appeared that the bottom of the stem had turned brown and I could see little white threads coming off it, like it was rotting. I took the plant out and sure enough the whole bottom basically broke off. I stripped off all the brown stuff on the stem. It had already sprouted a couple of roots from the side, I guess it did this when the lower roots started rotting. So I planted those roots into the gravel as best I could and I stuck the bottom of the stem back into the gravel. I hope it lives! Today one of the newly sprouted leaves has a funny look in one spot but other than that it's still living. What would cause rot to set in?

 

[VaughnH]

Plants require adequate nutrients, NPK and traces, a source of carbon (CO2, for example) and adequate light. Given those things nearly all plants will grow. So, you are likely to be short on at least one of those needs.