125L 2 discus, 1 black ghost

[Hedphelym]

My aquarium is 125L, i have 2 discus, 1 black ghost, and some tetras.

how often would i change 30% of the water?
i've now done it 1x week, but i'm having trouble with my plants, they just go brown, and transparent,(not all of them, but suddenly they loose alot of leaves etc) could this be due to the water?

My tank is a Juwel 125L, i have the default lighting that came with it, is this something i should do something about?

i have c02 in it, i also add iron and other things for the plants.
I also have trouble with algea, thin threads (kinda like fur), so currently treating that with some tablets i bought for it..

I do have a root in there too.

My discus is laying eggs every week, so they seem to have a nice time btw.

[Discus+us]

Hi there i have a Juwel 450 vision.
I think it would be better to change just 20% of the water, per week...
Yes, i know where your coming from in regard to the lights (ie) default lighting which are T8s. I've changed mine to T5s, but you can't just put different Tubes in, you need to buy the whole lighting unit. By changing
your lights to T5s and adding some light reflectors to the Tubes aswell, you will see a visible diference in the plant colour and their growth. Cut back on feeding your fish and/or plants and the amount of time you leave your lights on, 10 to 12 hours max no more than that per day, that will help out with the algae
I hope this helps you...

[Hedphelym]

thanks for the answer, i will follow that, and see how it goes.

I have set the light to go on at 09 in the morning and off at 10 at night.
i will cut back a little on that too, to see what helps..