# Hemianthus Micranthemoides VS Micranthemum Umbrosum



## spypet (Sep 15, 2006)

Hemianthus Micranthemoides; pearl weed, baby tears are what's used by most hobbyist here in the USA as it's a true aquarium plant that is relatively easy to grow. Umbrosum is pretty much the bog variety of the same plant, which grows slower than baby tears. baby tears can grow vertically, horizontally, in mounds, it all depends on lighting and how you prune it. so if you are doing an aquarium, you want HM, if you doing a terrarium MU would hold up better. these plants are extremely sensitive to petrochemicals, so any plastic or nylon in contact will make them melt. algaes likes living on baby tears, so be sure your tank is not algae prone before getting this plant.


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## bharada (Mar 5, 2004)

Hemianthus micranthmoides...
















Micranthmum umbrosum...









Sorry. No close up of the umbrosum. But you can see from the photos that the umbrosum has a rounded leaf compared to the lanceolate shape of the micranthemoides.

Also, their growing patterns are very different. The micranthemoides will spread vertically and horizontally (via runners) at the same time. In good growing conditions it can form a solid hedge, filling up as much space as is available to it. However, when it gets this dense the inner stems will yellow and die back from lack of light. So it's best to trim this plant regularly in order to maintain the bright green leaves. But even if you do wait too long to prune, and hack it down to the yellowing stems, it will grow back in short order.

The umbrosum, OTOH, will grow into a vertical bush. The anchoring stems tend to rot and break once the plant has reached sufficient volume to cut off light from reaching the bottom of the plant. At this point you will need to grab the floating bush and reanchor it in the substrate.


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## carpenoctem (Aug 26, 2005)

Thanks very much for the info. I knew there were differences between the two, but for some reason I started thinking their common names were interchangeable and therefore they were actually the same plant. Fortunately, I have Hemianthus Micranthemoides which is the more adaptable of the two.


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## stevenlau (May 26, 2009)

spypet said:


> ...these plants are extremely sensitive to petrochemicals, so any plastic or nylon in contact will make them melt...


Sorry to bring up the old thread but I really like this plant and have tried to grow it in almost a year with no good results. I've tried to so much effort but all were in vain.

Someone please tell me that any plastic (as stated by spynet above) will make this plant melt? What about our filter input and output parts that made from plastic will make this plant melt? Should change the part with glass made part such as ADA Lily Pipe? What about petrochemical? Nylon fabric? Some of my fish nets (I think) are made from nylon...is this the possible cause of my melting HM?

Thank you


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## Darkblade48 (Jan 4, 2008)

Not too sure where that came from, but I have grown HM fine with plastic things in my aquarium (filter pipes, etc).


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## Sharkfood (May 2, 2010)

I definately have not found HM to be sensitive in any way. It's easily the fastest growing aquatic plant I have ever seen. I used it as a carpet in my 65g and one plant made a whole tank carpet in maybe 2 months. I ended up pulling it out because I didn't like trimming it twice a week. I still had some grow back out of the substrate for weeks after I pulled it all up. It is a nice looking carpet though. 

I've never heard of the plastic thing. That's weird.


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## sewingalot (Oct 12, 2008)

I suspect this plastic thing is a little far-fetched. The only time I have melting issues with these plants is when my nitrates get too low. In my opinion that makes them excellent indicator plants.


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## stevenlau (May 26, 2009)

sewingalot said:


> I suspect this plastic thing is a little far-fetched. The only time I have melting issues with these plants is when my nitrates get too low. In my opinion that makes them excellent indicator plants.


 Hmm...nitrate...I thought so too. I think I have problem with my Sera Nitrate Test Kit. I never have a nitrate test result below 30ppm each week usually is between 40-50ppm but I only dose around 15ppm per week of KNO3 even once I stopped dosing nitrate in a whole week and still the result was very high. I test my water source and it is 0ppm of nitrate and maybe this test kit is the culprit here. I will bring my tank water to be tested in a lab soon...


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## sewingalot (Oct 12, 2008)

Yeah, the test kit is probably off by the sounds of it, especially if you are dosing one amount and getting a really high reading. These plants are serious nitrate hogs. Once established, I have to dose nitrates daily just to keep up with them.


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