Do you like waterweeds?

[AtomicSunfish]

Do you use waterweeds (Egeria densa and Elodea canadensis, formerly Anacharis) in your aquaria? How are they for removing ammonia and reducating nitrate buildup? How demanding are they in terms of lighting and nutrient needs? Are simple LED lights enough for them, or do they need some kind of special grow lights?

I had a bunch of Elodea in my 55g, but most of them dissolved away. I don't think that's due to nutrient deficiency, since the bioload was pretty high in there, so I think that was because the tank was too dark. So, I moved some to my 29g which had better lighting, and they seemed to grow a bit better there. I recently put some in my well-lit 10g African dwarf frog / bladder snail tank, to help absorb nitrogen from uneaten food, and they seem to be growing better still. Do you think that's mostly due to more light, more fertilizer (waste), or both factors about equally?

Nevertheless, I'm kind of surprised they're not growing super-fast in the well-lit 10g and 29g tanks. I thought waterweeds were some of the hardiest and fastest-growing aquarium plants out there. Are they pickier and more slow-growing than I thought? Would you recommend some other kind of plant instead?

[The-one-and-only-flo]

Waterweeds are very easy to keep, grow very fast and are often used to counter the nutrition spike of new tanks. Lack of nutrition slows down their growth and can kill the plant.

[jwcarlson]

I've got quite a bit of elodea in a tank that's below a bunch of dwarf water lettuce, I believe that the leaf nodes get stretched out a lot probably due to lack of light.  But it doesn't seem to melt because of lack of light.  Though a total lack would obviously eventually kill it.  I don't fertilize the tank and it's not particularly heavily stocked.  It's just a big jungle-y mess.  I've got bits and pieces of it in other tanks, but they do not seem to grow that quickly in my tanks.  My guess is that's because of low nitrogen availability in my tanks.  I change a lot of water and rarely fertilize anything.  

As far as other types of plants that might work for you.  Hornwort grows well for me and PSO (pogostemen stelatis octopus, not sure on spelling) grows OK for me as well.  Dwarf water lettuce is good, too.  A popular aquarium plant that gets overlooked easily and removes nitrates really well - pothos.

[AtomicSunfish]

Ok, so it sounds like if your tank is cycling properly, then that puts Elodea at a disadvantage and makes it grow slower?

[jwcarlson]

On 5/6/2024 at 3:51 PM, AtomicSunfish said:

Ok, so it sounds like if your tank is cycling properly, then that puts Elodea at a disadvantage and makes it grow slower?

It's probably just a matter of nitrogen availability.  Do you have a picture of the tank?  I don't think it's probably a light issue.  

[clownbaby]

YES! Elodea canadensis grows near me and it grows well in tanks... TOO WELL!!! If you want a quick growing plant that spreads, this is the plant for you. This thing got huge and started growing like crazy within two weeks, I had to remove it LOL. It definitely is a "weed"!! Pondweeds are good choices too. I have richardson's pondweed (Potamogeton richardsonii) in my tank and it is super cute. It is native too so I got it from a local stream. It grows well as a midground plant. Check out what pondweeds grow near you... there are many good options!

[Tanked]

I've has mixed results with Elodea/Anacharis. I found it hard to get started initially. It is considered a low light plant, but it definitely likes light.  The Elodea in the outdoor tub looks like a completely different plant when compared to the aquarium plants.  It eventually faded away in the lowest light tank.  In the brighter tank, it became a floating plant with an impressive root system, that eventually choked out the Hornwort!  Some of mine faded away naturally, and unfortunately the fish ate the rest.

[AtomicSunfish]

On 5/6/2024 at 4:21 PM, jwcarlson said:

It's probably just a matter of nitrogen availability.  Do you have a picture of the tank?  I don't think it's probably a light issue.  

Yes, here is a picture from this morning. This tank is a 10g with one African dwarf frog (hiding), and I just added the ~20 guppies. But the Elodea are pretty small. You can see some new growth in the back left, but other than that, I think they’re staying short. Do they have to lay down roots first before they can grow?

[jwcarlson]

I have some stuck in substrate, but it also grows just floating around, I think.  It will grow really long roots if left floating.  You could uproot a couple of them and let them float up closer to the light and see if they grow better.  But if all you had was a frog in there, it probably didn't create enough bioload for it to fuel good growth.  You might see it start growing now with more fish.

[AtomicSunfish]

On 5/7/2024 at 2:28 PM, jwcarlson said:

I have some stuck in substrate, but it also grows just floating around, I think.  It will grow really long roots if left floating.  You could uproot a couple of them and let them float up closer to the light and see if they grow better.  But if all you had was a frog in there, it probably didn't create enough bioload for it to fuel good growth.  You might see it start growing now with more fish.

Ok, thank you. Yes, I think bioload was the problem, because that frog is the last of 5 … the other four died of bloat, which I’m now convinced was due to poor water quality. Even with bladder snails cleaning up after them, their uneaten food and waste released too much ammonia and fouled the water. That’s when I realized Elodea or other plants could help with that. Well, hopefully the current community will work better. Thank you!