what is wrong with my stargrass

[DX]

the stargrass in my tank does not look very healthy. New leaves have very pale green colour while old ones become wither. My tank is about 100 liter and is placed near a window. I have a tank light with a normal fluorescent tube (18w?) and I turn it on between 6pm and 10pm. Would the direct sun be a problem? Or the lighting is not enough for growing the star grass? or disease?

I have another puzzle. I usually see fresh nice looking plants in fish shop. But I always wonder what they look like when wither and die. Will they look like those of mine in the photo?

[antwan]

18W over a 100L tank really isn't that much for growing plants. Also, a photoperiod of just 4 hours a day really isn't that much, try for 8-12 hours and if you can, try adding an extra light or two over the tank, your plants will thank you for it.

[fishboi]

yep i second that i set my on a timer for 12 hours.

[Caryl]

I'll third it

Not enough light.

[DiverJohn]

I 4th that!!!

Also my stargrass looks a bit like that, keep it trimmed back and it grows nicer. Its also quite fast growing under better light so without going OTT you MAY need a bit of fertilzer to help with micro nutrients.

[Luke*]

I fifth* it, you want ideally 1w/litre, can get away with 0.5 though or a bit less if you have fertilisers and CO2. To answer your second question, the shop plants always look good because they get them in fresh from the growers and then sell them on before they have a chance to die. Use to puzzle me too why shop plants look so good with just the usual fluros that most people have at home.

*edit..you just beat me DJ by the time I hit submit

[antwan]

Quite a lot of the fish shop stem plants are grown emersed too so will change their appearance when grown under water.

[evilknieval69]

My stargrass is growing hard in a 240L tank ATM. it only has 70 W of light on it for now. I believe the secret is co2.

Get another tube or two and setup a DIY co2 unit if you are realy keen on your plants

[DX]

Thanks for your reply.

I talked to a friend about the problem of my plant. Here is her advice,

"Too much light will kill the plants and encourage

algae. The dying plant material will also encourage the algae and

that is why you should throw it out ASAP.

The links talk about artificial light which would be only a small

fraction of the sunlight your plants are getting near the window. Move the tank

away form window "

I believe she knows what she is talking about, as she did a PhD about light, water plant and new zealand lake. And I also believe you guys know what you are talking about, as you have good health plants in your tank. really confused. :roll: :roll:

[Luke*]

You need more light bud, if not totally dead, your dying plants may even recover.

[Plantman]

4 hours of light alone is not enough and plus the fact that it is on 18 watt is really low for your 100 l tank.

supplimenting the plant with sun light cause a unbalance effect.

the strong ray from the sun cause the plant to work harder for nutrient but it is not able to do so. Algae will be able to absolve the nutrients a lot faster than your plant. your friends know what she is talking about.

one suggestion is to move away from the sun, increase your watt and have at least 8-10 hours of exposure.

if you do not want to move your tank. than CO2 is needed to encourage you plant to compete against the algae for nutrient.

All the best.

[alanmin4304]

Stargrass needs a lot of light. The usual problem people have is letting it grow too tall and it blocks the light to the bottom of the pLant and the leaves go black. Keep it short. give it lots of light and it will grow that well you will be able to apply for a PhD.