Q: I was told keeping a plant in my betta's jar can help the water quality, but the jar is small and I do not use gravel. What plant would you recommend I use and can it really help?

above question submitted by Jennifer, Santa Fe - NM

Well, Jennifer you are in luck because I recently tested the efficiency of Java Moss and have great news for everyone! JAVA MOSS may very well be a betta's BEST FRIEND! :)

Java Moss (Vesicularia Dubyana), is an unusual plant because it does not have roots to speak of, will sink to the bottom, will grow like weeds under the crappiest conditions (no gravel, low light, no fertilizer, most water temp ranges and most PH ranges) and doesn't look too shabby either ;).

What's most is, the Moss loves stagnant water and lots of nitrite. In fact it will THRIVE on high nitrite levels and left over food and fish poopies. 

So add the two above and you can see how Java Moss would be the PERFECT plant for a betta jar: NO gravel, stagnant water, low light (in many cases) and LOTS of nitrite! Your betta's bowl is a Java Moss heaven. 

OK, so the stuff will grow and probably do pretty well. That brings us to the next (most important question): Will it clean the water? And if so, how well?

So I put Java Moss to the test. I did a water change on two 1/4 gal jars, each housing a female of similar size. I added a small clump of Java Moss in one jar only, leaving the other one Java Mossless (if I may say LOL).

On day two I did a nitrite test:

java moss nitrite test2.jpg (41311 bytes)

Test clearly indicated that both jars were still within safe range (blue color)

A few more days went by and on day 5 (day of next water change), I did the same test again:

java moss nitrite test1.jpg (41589 bytes)

Now compare the test tube of jar 1 which had the Java Moss in it (blue in color - completely safe range) to the one on the right which did not have the Java Moss in it (purple in color - high nitrite levels - BAD for fish). The nitrites level went up the roof in just 3 more days (while they appeared fine on day 2). SO very clearly, the fish with the Java Moss had much much better water quality and a highly decreased chance of getting sick.

I rest my case your honor :).

A few more things betta keepers should know about Java Moss:

  • No, Java Moss can not REPLACE water changes! You will still have to do them but the water will stay healthier in between them :).

  • Yes Java Moss will sink on its own and stay at the bottom, no need to use plant weights or rocks/gravel

  • No, it will not easily attach itself to a plastic smooth surface especially with weekly disturbances when you do your water change

  • Yes if you are using a tank with gravel, it may attach itself to the gravel, rock or driftwood and soon take over your tank LOL.

  • No, it will not make it harder to do your weekly jar water changes. I have found that the Java Moss always falls in the fishnet first, followed by the betta who ends up lying on top of that java mattress :). Allowing you to change the water in the jar and then gently dump both plant and betta back in. Plant will slowly sink down, betta will oftentimes hide in it.

  • NO it will not tear the betta's delicate fins. Java Moss is very soft and has no pointy parts which could cause the fins to tear. :)

  • No, it will not make it hard for bettas to find their foods. My bettas have been able to find even small food particles fallen in the moss and ate them. Even if they did not, the Java Moss will enjoy the extra food :).

  • No it will not make the water dirty or foul it. Although Java Moss does produce plant byproduct, it usually gets taken care of when you do the water change. Small dead plant particles will be flushed through the net while the rest of the plant is saved.

  • Java Moss will grow fast, so don't put too much in the jar, make sure to leave LOTS of room for Mr. Betta. Do not suffocate him in a huge pile of Moss! if it grows too much, discard the extra.,No need to prune etc, just tear off extra and toss.

  • Java Moss is easy to divide. Simply take your clump, pull a bit with your fingers (it will come apart immediately) and place it in the jar and Voila! You are done.

  • warning: if a betta is sick do not use the same moss for another betta, as plants will carry bacteria from one jar to the next. So assign each betta his own plant and discard any plant that has been exposed to a sick fish.

Because of all above I have decided to offer Java Moss to our customers, and it is now available when you purchase bettas from us. Simply check the "I want a starter clump" (or 2, 3,4 etc) and the moss will be included in your box along with the fish! Makes it easy and hassle free. I hope you all have as much luck with it as I have, but worry not, if you have a truly black thumb LOL and you somehow manage to kill it, it is very cheap to replace :) and there's plenty more where that one came from :)).

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About me: I am a member of the IBC, founder and President of LABS  (Los Angeles Betta Society) 
and have been helping the betta community through this website for over 6 years now. I have over 

170  spawns and  3000 shipments under my belt 
and I was recently  featured on   A N I M A L    P L A N E T. 

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