Plants in Softwater tank

[Phil_1983]

Hello everyone,

I am currently planning a soft water aquarium for an Apistogramma and some tetras/pencil fish. The aquarium will have a capacity of around 180 liters and a base area of 100 cm x 40 cm.

As I would like to achieve a black water look, I am wondering whether my plan is feasible. I would like to use some plants (E. Bleheri, E. Griesebachi, H. Tenellum, N. Lotus, S. natans, and L. Lavigatum). I am looking for something, resembling Valisneria in addition. So if you have any idea here, that'd be great, too.

Does anyone have any idea whether these plants could thrive in very soft water? I plan to use RO water exclusively. I don't know how I can add at least some minerals to the water for the plants without using GH+. Therefore, I would like to hear about your experiences in this regard.

 

[MacZ]

Eleocharis sp. or Cyperus helferii are options to mimic the visuals of Vallisneria. Oooor you simply use Vallisneria.

I don't know how I can add at least some minerals to the water for the plants without using GH+. Therefore, I would like to hear about your experiences in this regard.

I only added liquid complete fertilizer (in my case Specialized Nutrition by Tropica, but any comparable product will do!) in minimal dosage (using Darrell's duckweed index) until the combination of rotting plant material (botanicals/leaves), leftover fish food and the excretions of the fish became enough to sustain the plants.

And my advice for plants in a tank focused on fish: If a plant species doesn't work and gets taken over by another species or simply withers away, let it happen and let nature run its course. In such a case you would only put work and wnergy into a battle you won't win.

 

[anewbie]

Sadly my vals cover the entire aquarium with inert substrate and no fertilizer of any sort. I try using a paddle to train them but they ignore me. Just keep the light low.

 

[Phil_1983]

Eleocharis sp. or Cyperus helferii are options to mimic the visuals of Vallisneria. Oooor you simply use Vallisneria.


I only added liquid complete fertilizer (in my case Specialized Nutrition by Tropica, but any comparable product will do!) in minimal dosage (using Darrell's duckweed index) until the combination of rotting plant material (botanicals/leaves), leftover fish food and the excretions of the fish became enough to sustain the plants.

And my advice for plants in a tank focused on fish: If a plant species doesn't work and gets taken over by another species or simply withers away, let it happen and let nature run its course. In such a case you would only put work and wnergy into a battle you won't win.

Thanks again.
I do not want to use Vallisneria, because I had real bad experiences with those in low KH-Water. But i will have a look at the alternatives you just mentioned.

Okay, the Tropica fertilizer sounds perfect, since i can buy it locally. I already read Darrels post partially and will deep dive there this weekend.

Of course, the plants are not my focus. I just thought it couldn't be a bad idea to listen if anybody has experience with the mentioned plants. You know, I don't have to buy plants that are not going work, and would spend the money on others.

 

[Phil_1983]

Sadly my vals cover the entire aquarium with inert substrate and no fertilizer of any sort. I try using a paddle to train them but they ignore me. Just keep the light low.

Oh, for real? This sounds really interesting.
You know, I saw pictures of your tank and that is where my question regarding alternatives to valisneria came from.

 

[anewbie]

I find the regular sort and grow well but the nana sort work best - yabba creek is slightly nicer but in 2 tanks i ahve regular val and it grows well enough and i have the corkscrew variety in one aquarium - it grows well enough but the tops sometime decays.

I would go for the nana or yabba creek (which has more pattern to the leave) if you find it. Of course you can take this approach (frogbit):

The aquarium is quite dark almost too dark for the plants to grow because of the frogbit cover - the camera of course attemps to normalize the light level making it look lighter.

There are 20 or 25 green light tetra in there but they like hid from me for 12 to 18 months so i thought they all left even in this picture you can't find them but they are in there.

This is an aquarium with regular vals:

The aquariums is 48x24 and most of the vals are planted in the very back with leaves over 60 inches long. This is NOT jungle val but the regular sort.

This is nana val:

 

[Phil_1983]

This is crazy. I unfortunately have no pictures of mine, because the vallisnerias were done in within two weeks. If I could get this results in a softwater and nearly-no-KH-tank, I'd be pleased. I definately am going to try it. Thank you!

 

[dw1305]

Hi all,

This is crazy. I unfortunately have no pictures of mine, because the vallisnerias were done in within two weeks. If I could get this results in a softwater and nearly-no-KH-tank, I'd be pleased. I definately am going to try it. Thank you!

I've never had any joy with Vallisneria spp. either, but I don't whether that is lack of nutrients, or lack of alkalinity.

Cheers Darrel

 

[anewbie]

Hi all,

I've never had any joy with Vallisneria spp. either, but I don't whether that is lack of nutrients, or lack of alkalinity.

Cheers Darrel

If it helps any the one with the frogbit and val nana are ec 20ish and the one with the regular val is ec 40.

 

[Glass Box Diaries]

I am looking for something, resembling Valisneria in addition. So if you have any idea here, that'd be great, too.

Cryptocoryne crispatula var. crispatula might work, I have it in soft water tanks and it works perfectly fine. Being a variety of crispatula, it has long, thing leaves similar to val.

I havent kept it myself but Cryptocoryne crispatula var. balansae may work too but I have heard its leaves can develop a more wrinkled look when kept in soft water.

 

[Phil_1983]

Hi,
how do you guys deal with magnesium/calcium deficiancy in those softwatertanks running on pure RO? Do I even need to care?

 

[MacZ]

You don't have to care unless all plants show chronic deficiency. The usual course is providing it with the fertilizer at first and when the mulm from the botanicals andleaf litter piles up, a lot of nutrients accumulate in the substrate and the fertilizer can be faded out. Takes some patience, though: I was able to whean the system off fertilizers after about 10 months to a year.

 

[Phil_1983]

Okay, that sounds good. Will do as you say, MacZ. I again appreciate your help!

 

[MacZ]

My pleasure!

 

[dw1305]

Hi all,

how do you guys deal with magnesium/calcium deficiancy in those softwatertanks running on pure RO? Do I even need to care?

You can just add fertiliser via the <"Duckweed Index">, plants suitable for soft water have very low nutrient requirements.

Cheers Darrel

 

[Phil_1983]

Okay, that makes perfect sense.... sometimes I really tend to ask "stupid questions". Thanks for answering anyway, Darrel!

 

[MacZ]

I can really recommend the duckweed index. I use it too with excellent results.

 

[Phil_1983]

Yes, I read parts of it and I like it so far. I was just curious, because the Tropica Specialized fertililzer doesn't mention Ca in its "list of ingedrients".

 

[anewbie]

I haven't noticed any real need to fertlize plants in a blackwater environment. I do use root tabs now and then with specific plants but beyond that i tend to have a let nature take it course approach. I just posted these image that shows an aquarium transition over a year and while it had a bit of a hair algae problem when i first put the vals in there since they had to adapat from tap water to blackwater it has mostly balanced out:

blackwater tank cycling?

No, new blood in all of that time. In 2012 I collected and brought home 3 specimens of each sex. I got 2 breeding pairs and a lot of offspring. These were crossed with the 2 unpaired fish and with different broods. All bred true to the wild form for about 6 generations (~5 years). Then I would...

apistogramma.com

Unfortunately i did not take a picture when i added most of the plants - the big bear and s repens have been in there most of the year so are well established - the hydro on the left is a bit newer - as it was added mid oct. 2025 (so as we can see even without any nutrients it is a very fast growing plant) - the buces were added around may 2025.

So the only plant i would question in terms of establishment would be the hydro but - it is not unusual for the stems to rot after a year or two and require replanting so i'm waiting to see if this one does the same - though it seems to have some bottom sprouts which i've not seen very frequent - if it does then i have hope i won't have to deal with the rotting stem issue.

Unlike most of my aquariums - i've been aggressive at pruning the val to keep it from spreading across the entire aquarium as i prefer it to just be on the right edge even if i did leave a few of the runners that reach the back of the left side (i mostly pull anything that is not against the back though i'v started to thin even the back a bit as that plant can take over the entire aquarium pretty quick). I've been shifting mostly to nana val as at least the thinner leaves are less dominant.

This is a close up of the s. repens; i have some older picture of the s. repens that shows how it has been transitioning over time. I will not that this is a more difficult plant to grow and i've kept the light a bit brighter on this aquarium to encourage it though that has some negatives.

 

[MacZ]

@anewbie : Let's be clear, your tank is definitely true softwater but not blackwater. Also you have quite high stocking densities, and consequently a lot more nutrients coming from fish food and wasteproducts.

I was just curious, because the Tropica Specialized fertililzer doesn't mention Ca in its "list of ingedrients".

Interesting, because the bottles listed Ca just two years ago (that's when I bought the last bottle myself), so they must have changed the ingredients.