# Need Help with Hygrophila polysperma



## mrbelvedere (Nov 15, 2005)

trfjason said:


> As the title states, I need help with this plant. The stems tend to rot in the bottom part. What did I do wrong? What should I do to prevent this problem?
> 
> Thanks.


Increase lighting or put root fertilization tablets under the plant. A combination of the two would be best.


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## Momotaro (Feb 21, 2003)

I am thinking it is more of a lighting issue and less of a root fertilizer thing.

How much light is over the plant? Are the bottom portions of the plants heavily shaded?

Mike


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## trfjason (Aug 10, 2006)

A 20W 6700K is right above the plant. There are many leaves on the top that covers most parts of the bottom. I was thinking if there are enough light for the bottom too. Should I remove some leaves to get more light to the bottom? Do I have to move some stems so it is not as crowded? 

I will place a Flourish Tab and see what happens.


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## mrbelvedere (Nov 15, 2005)

Momotaro said:


> I am thinking it is more of a lighting issue and less of a root fertilizer thing.
> 
> How much light is over the plant? Are the bottom portions of the plants heavily shaded?
> 
> Mike


True, but root fertilization usually helps keep lower leaves robust when light levels are adequate. In this guy's case, sounds like a light problem.


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## Ryzilla (Oct 29, 2005)

what size tank do you have? What is your water parameters? I have hygro poly green growing in three different condtions without any problems. It is in a high tech tank 30g 154w with a ph of 6.4 and kh of 6.5.. I have it in a lowtech 50w over a 38g no Co2 no ferts ph of 6.0 kh practically nothing.. It is also in my shrimp tank 10g 15w, no co2, ph 7.6 kh 6.5. It all grows fine. There must be some factors here that you have not investigated enough. We need more info. Hygro poly giant or green should grow in the worst of cinditions. This is the first time I have heard of anyone haveing problems with this plant. If you have sunset hygro then that may be a different case.


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## rrguymon (Jul 10, 2005)

When I haad this plant I had the same problem when I first got it. The roots would mush away. After it had been in my tank a while and I had pruned out all the orginal plant it stopped doing it.

I think once all the mass of the plant formed in your water it will go away. It did in mine.

Rick


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## trfjason (Aug 10, 2006)

Tank size is 31G, pH 7.0, KH 5, DIY CO3, 40W 6700K, regular iron fertilizer (two times a week), just started dosing potassium. 

I know this is a easy plant to grow, but I still don't understand why it's giving me problem. 

I have Alternanthera reineckii and I have no problem with it.


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## trfjason (Aug 10, 2006)

rrguymon said:


> When I haad this plant I had the same problem when I first got it. The roots would mush away. After it had been in my tank a while and I had pruned out all the orginal plant it stopped doing it.
> 
> I think once all the mass of the plant formed in your water it will go away. It did in mine.
> 
> Rick


I just took out the whole plant, remove all the old rotted stems and roots from the substrate, cut out all the rotted stems, and replanted it. 

I hope this problem will go away, as it is getting annoying. 

I also added some potassium. Will this help the stems?

I have two Amazon Swords beside it, will they absorb all the nutrients so it's giving the Hygro problem?


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## czado (Jun 24, 2006)

> Should I remove some leaves to get more light to the bottom? Do I have to move some stems so it is not as crowded?


I think you should. When stems get too crowded they tend to choke themselves out. By the sixth trim of R rotundifolia I need to thin some stems, for example. You don't have to uproot and could just trim close to the substrate line to buy time if wanted.

If your old leaves aer yellowing then dropping I agree you need to adjust dosing and use H. ploysperma as an indicator plant. Most agree this indicates a nitrogen or phosphorous deficiency.

HTH


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## trfjason (Aug 10, 2006)

They are not as crowded as before. Two days after replanting, I noticed 2 stems started rotting. I don't think it's a light issue. What else can it be?

This is suppose to be a hardy and easy plant to grow, but I am having problems.


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## medicineman (Sep 28, 2005)

It might be the substrate. I used to fail miserably during my early days because of my substrate (and nobody knows whats wrong). I even have very strong metal halide but still the bottom part would rot away. Changing my substrate into appropriate type works like magic, everything grow as supposed to be.


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## jasonh (Oct 26, 2003)

My wife and I can grow this plant like a weed in just plain pool filter sand with a little peat, so I doubt it's substrate. I'm more inclined to say lighting. 40w over a 31G isn't much....


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## IceH2O (Sep 29, 2006)

Its not even 40 he said 20...You're going to be hard pressed to grow anything at less than 1 wpg...Give the Alternanthera reineckii time, its a high light plant, it'll die also. Even java Fern would struggle at that wattage.

Try adding more light.. Go to Home Depot or your equivalent and buy a double strip flourescent. If you can get T5 bulbs then even better. 40 watts of T5 will allow you to grow low light plants. If you could build a canopy and make it 3 bulbs you'll be close to 2 wpg and be able to grow some of the medium light type plants


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## trfjason (Aug 10, 2006)

The whole tank is covered by two 20 watt, so a total of 40W, but what I mean is one of the 20W is right on top of the hygro. I have had the Alternanthera reineckii for more than a month and I don't have problem with it at all, new leaves grow all the time, and I took some cuttings and plant it on the bottom and it grows. If I don't have enough light, I think the plant will not grow. 

I actually have another type of Hygro, Hygrophila corymbosa ''Siamensis'' and I have the same problem with that too. I managed to get 2 stems grow without that problem, but the rest sometimes have the stem rot at the bottom.


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## IceH2O (Sep 29, 2006)

My bad..I missed that part in the post before mine.

Mine grows like a weed needing trimming every other week and I use sand and only have 1.75 wpg on my tank.

But I do dose my tank with dry ferts, traces and excel. 


Hygro isn't really a root feeder so I don't know that tabs will help much, they are a water column plant. You'll notice when they start doing well the roots will come out of the stem even halfway up the stem.

Try planting them in bunches of 3 a couple of inches apart. That should keep them uncrowded and give good light to the lower parts.

Do you use gravel? Some people say the sharpness of gravel cuts the stem causing the rot.


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## trfjason (Aug 10, 2006)

Yes, I do use gravel mixed with Laterite. I might try putting more Laterite by the Hygro and see what happens. The Alternanthera reineckii has roots coming out half way up the stem. It's growing quite well, I think it's easier than the Hygro since it's giving me so much problems. 

It might be the gravel, but they don't look sharp.


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## ringram (Jan 19, 2005)

To grow those plants successfully, you will need more lighting. I would bump it up to at LEAST 2wpg, so 55-60w. You would probably do ok with a 55w Power compact, but it still probably wouldn't help high light plants from dying. Just to give you an example, I have hygro polysperma growing and doing well in my 20g and there's 110w of PC light over it.


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