why do my plants die

[sushi]

Hi. I've got a commuity tank with a lot of plants. Whenever I buy plants from my lfs they look really pretty for about a week and then they just start losing leaves and going brown.
The ones I buy are 'cuttings' off other plants, they don't have roots. If they live long enough they get roots, but 90% of the time they don't.
I was wondering if anyone knows why this is. Does the vitamin tablets and liquids that you can buy for plants (iron) actually help. Would that make my plants grow roots quicker, would it help them to survive???
Would it be better if I got them established in another tank before putting them in a community tank???
Please help me. Thanks for any advice in advance.

 

[Dubby]

Hi Sushi:

Can you tell us what substrate and how much lighting (in watts) have you got for the tank?

 

[Tempestuousfury]

Also, do you allow the plans to grow roots by rubber-banding them to anything or to you just bury them into the substrate.

If you don't get adequate help, I suggets you gte plants with well developed roots. That way you'd be able to tell if it was the tank parameters or the plants that were causing the problems.

 

[Lateral Line]

Cuttings of stem plant are generally more light demanding then some rooted plants, but they are otherwise pretty easy to grow. If you are not succeeding, you almost certainly do not have enough light for them. If there is not enough light, adding fertilisers or other things will not help, the plants need light to power their metabolism.

To get "Medium" light, you need about 2 Watts of full spectrum, (5500K - 6500K) fluorescent light tirned on for 10 - 12 hours a day. We don't know enough about your tank to really suggest other plant types yet.

 

[sushi]

hello. The substrate (i'm not sure what that is, I'm assuming it's what's on the floor of my tank???) is pebbles from the beach (they're clean, and have been in tank for about 10 months) I heard that big pebbles don't help, I think mine may be too big. They're about 1cm diametre, most of them. I found a new place which has tiny pebbles that I can replace them with if nessescary.
The sticker on the underneath of my light says 20W. So I'm guessing that's not enough hah???
Some of my plants grow well. Like the ones like thick grassy leaves that spike up. They're white and green. ANd there's one other sort that seem to be fine. But the rest with fragile looking leaves always die and lose there leaves.
I just want to know what is causing the dieing. Or if there's hardier plants, like the ones I have that will grow and the fish wont eat.
Thanks for your help.

 

[Dubby]

You definitely need to get more lighting (as LL has said). 1cm dia pebbles will not allow plants to root easily. Go for smaller pea sized gravel or sand. (childrens playpit sand will do).

Good low light plants include Java fern, java moss, hornwort (floating), anubias and Egeria densa.

 

[M/ASC]

remember guys that plant roots only anchor a plant down, and do not gather nutrients like terrestrial plants do. it is normally recommended that you cut plant roots of if there are any on there so that plant can regow them to hold itself in place. aquatic plants take nutrients out the water through the stems and leaves because there is a higher level of nutrients there then in the ground.
Also lighting is very importatn as lateral line said, without enough light they cannot convert CO2 to carbs and will simply starve to death. in your size tank i would say you need atleast 3 if not 4 tubes to power it all off properly.
CO2 is also a major factor, to grow plants properly you need to add some kind of source for CO2, without this the plants will not be able to make carbohydrates in which to feed themselves(correct me if im wrong about the carbs, its been a while since college lol)

 

[Silly me]

uhm.. M/ASC..
First off most plans still uses there root for nutrients. I had a much bigger success rate with root tabs and nutrients ritch gravel that I ever had with any other type of fertilizer.. first off you'll always have some problem with rooted plants and stem plants in a clean gravel tank, also peddles of any sort will not do, you dont need a high nutrients substrate but you need 1-2cm sized gravel for propper rooting,

sushi lights is very importend, you'll need atleast 2watts fullspectrum lights for ever gallon of water, so you might need more than 80 watts..?

 

[spectre]

I agree fully with silly me. Most plants(especially the larger ones, swords, crypts, etc.) are primarily root feeders. The only plants that are totaly dependent on nutrients in the water column are floating plants.

Sushi,

Based on the info you have giving us so far I would say you need to do alot more research on planted tanks. There are numerous reasons why plants die, you need to determine which ones are viable in your tank. HTH