Best Plants for Veggie Filter / Sump

[bjorn]

I'm trying out different types of plants for maximum uptake of nitrates in my Sump. And wondering what plants would be suitable or best to use. I'm looking for maximum nitrate update but minimum mess and easy to maintain in a sump.

I originally used Elodea however they are very messy and just not working out very well. I've replaced them with floating plants (dwarf water lettuce) but not sure they are doing a better job.

I've also got a terrestrial Philodendrons plant growing with it roots submerged but it doesn't seem to be doing much and probably won't pull out much nitrates until it gets a lot bigger.

Would Marimo Moss Balls (cladophora sp) be of any benefit or do they use very little nitrates?

 

[Alastair]

Marimo moss balls are good, also cabomba which is a fast grower, amazon frogbit, water wysteria which is also a good nutrients drinker

 

[Michael W]

Alastair has already listed some good ones, I believe Elodea, hornwort, water sprite are also pretty good.

 

[Kyle Lambert]

Has anyone done a veg filter with say, tomatoes with the roots in the water? Just wondering if that nutrient rich water (which i use to water my plants outside after a water change) would be able to grow something edible. Basically a bit like hydroponics?

 

[Michael W]

Yes I believe it can be done, its just like how some people will use house plants on HOB filters etc

 

[bjorn]

Marimo moss balls are good, also cabomba which is a fast grower, amazon frogbit, water wysteria which is also a good nutrients drinker

I wonder how effective Marimo moss are, they would fit in very nicely in the sump with minimum mess.. it's slow growing though so would have thought it's not much nitrate they eat up. It could also work like a living filterwool I guess.. might have to try that!

Has anyone done a veg filter with say, tomatoes with the roots in the water? Just wondering if that nutrient rich water (which i use to water my plants outside after a water change) would be able to grow something edible. Basically a bit like hydroponics?

It's supposed to be possible, but it has to be plants that can have their roots submerged in water and no soil which is why I use Philodendrons, they are climbers and don't actually need any soil.

Unfortunately so far I've not managed to get nitrates below 8.

 

[dw1305]

Hi all,
I think Marimo balls (Cladophora) are a non-starter, they don't have access to aerial CO2 and grow pretty slowly, marine aquarists only use algal filters because of the scarcity of marine higher plants.

I'm surprised that Water Lettuce (Pistia stratiotes) isn't doing very well. There isn't really a Dwarf Water Lettuce, it all has the potential to grow into large plants if it gets enough light and nutrients.

It's supposed to be possible, but it has to be plants that can have their roots submerged in water and no soil which is why I use Philodendrons, they are climbers and don't actually need any soil.

Philodendron is a good one (from <Swiss Cheese Plant and other house plants | UK Aquatic Plant Society>).

But all plants can be grown hydroponically, these aren't mine, but we used to have a very similar set-up.

Unfortunately so far I've not managed to get nitrates below 8.

How are you measuring these? nitrates are quite difficult to measure accurately as you often get interference from other anions. In very HCO3- ion rich water the test could be measuring anything.

I also think you are really trying to do two conflicting things, you want low nutrient water for your cichlids, but you also want to add nutrients and CO2 to make your plants grow in the tank, and then you also have a vegetable sump filter to remove nutrients. It is an almost irreconcilable list of requirements.

This has been a strange thread for me, as I spend a lot of time on other forums trying to persuade "Rift Lake" cichlid keepers to add plants to their systems, rather than the opposite, but personally I'd concentrate on using the plants to produce very low nutrient levels in the tank. This is going to mean that the plants in the tank will be a bit scruffy and chalk covered, but in the lake itself all the shell beds, sand, plants etc are covered with a calcareous crust.


cheers Darrel

 

[bjorn]

Hi all,
I think Marimo balls (Cladophora) are a non-starter, they don't have access to aerial CO2 and grow pretty slowly, marine aquarists only use algal filters because of the scarcity of marine higher plants.

I'm surprised that Water Lettuce (Pistia stratiotes) isn't doing very well. There isn't really a Dwarf Water Lettuce, it all has the potential to grow into large plants if it gets enough light and nutrients.
Philodendron is a good one (from <Swiss Cheese Plant and other house plants | UK Aquatic Plant Society>).

I think you're right about the Marimo, just can't see it grow fast enough.

The Water Lettuce does grow but not sure the light in the sump is enough for it, I read that they require quite strong light? Will see how it goes but the older leaves are going yellow. Maybe that's just how they grow? They are putting out some huge nice roots though which the cherry shrimps are loving.

How are you measuring these? nitrates are quite difficult to measure accurately as you often get interference from other anions. In very HCO3- ion rich water the test could be measuring anything.

I'm using a electronic Nitrate Checker, I guess it could be out being a low reading.. But when using paper dip sticks it does colour up very slightly so there is some nitrates. I'm not too worried about getting it much further down, around 5-10 should be fine but it's only stocked by half the amount of fish I plan to have eventually. So there is not a problem at the moment but keeping it around this level when it's fully stocked might be harder. The other reason is that I don't won't want to do big water changes as it's a very large tank. 25% every other week is my aim.

Hi all,
I also think you are really trying to do two conflicting things, you want low nutrient water for your cichlids, but you also want to add nutrients and CO2 to make your plants grow in the tank, and then you also have a vegetable sump filter to remove nutrients. It is an almost irreconcilable list of requirements.

In my mind it's not conflicting. I want to keep low nutrients for the cichlids while also keeping some plants that look nice. I don't need or want massive fast growth, just something that looks healthy and good. As the stock of fish increases the plants in the sump and in the tank will hopefully keep nutrients sufficiently low to avoid having to do large water changes each week. The only "nutrients" I add are Micro / Trace elements, no macro nutrients. The only other thing I add is Cichlid trace solution and Rift lake salts. I just don't think there will be enough plants in the tank to keep nutrients down on its own. (Eventually there will be 2x Lotus, 2-3 clumps of Cyperus and 1x Aponogeton crispus.)

This has been a strange thread for me, as I spend a lot of time on other forums trying to persuade "Rift Lake" cichlid keepers to add plants to their systems, rather than the opposite, but personally I'd concentrate on using the plants to produce very low nutrient levels in the tank. This is going to mean that the plants in the tank will be a bit scruffy and chalk covered, but in the lake itself all the shell beds, sand, plants etc are covered with a calcareous crust.

Well, I want clear water and clean plants.. rather than being a true representation of the lake.

 

[dw1305]

Hi all,

The only "nutrients" I add are Micro / Trace elements, no macro nutrients.

This is what I don't understand, you aren't adding any macro-nutrients, but you intend to add CO2. Whilst CO2 is often the limiting nutrient if you have low nutrient levels of nitrogen (N) and potassium (K) growth will be limited by these rather than carbon availability. Phosphorus is needed in smaller amounts by plants than N & K, but PO4--- availability is reduced at high pH by the formation of insoluble calcium phosphate complexes. Other elements like Iron (Fe) are always going to be in short supply in very alkaline water, even when they are added as chelates. Iron hydroxides will form as soon as any FE+++ ions arise from the photo-degradation of FeEDTA etc. The same applies to the other elements that are of limited availability at high pH, manganese (Mn) etc..

The other reason is that I don't won't want to do big water changes as it's a very large tank. 25% every other week is my aim.

I'd go for a larger volume of water changes, even with a large plant mass. Water changes have a whole range of benefits.

cheers Darrel

 

[bjorn]

Hi all,
This is what I don't understand, you aren't adding any macro-nutrients, but you intend to add CO2. Whilst CO2 is often the limiting nutrient if you have low nutrient levels of nitrogen (N) and potassium (K) growth will be limited by these rather than carbon availability. Phosphorus is needed in smaller amounts by plants than N & K, but PO4--- availability is reduced at high pH by the formation of insoluble calcium phosphate complexes. Other elements like Iron (Fe) are always going to be in short supply in very alkaline water, even when they are added as chelates. Iron hydroxides will form as soon as any FE+++ ions arise from the photo-degradation of FeEDTA etc. The same applies to the other elements that are of limited availability at high pH, manganese (Mn) etc.. I'd go for a larger volume of water changes, even with a large plant mass. Water changes have a whole range of benefits.

cheers Darrel

Ah but this is why I'm asking! So what you're saying is that CO2 is not a issue or limiting factor in my situation due to other restricting factors? If so, it's pointless for me to supply any Co2 and might as well just go with very low light or lower it until the plants stop de-calcification (or at to a point were it doesn't look too bad).

I do understand large water changes are good, but on a very large tank that's not practical.

 

[foxfish]

I am a bit confused! why would you want to reduce the Nitrate levels?
Virtually all of us on the forum feed our plants so they grow healthy?

 

[bjorn]

I am a bit confused! why would you want to reduce the Nitrate levels?
Virtually all of us on the forum feed our plants so they grow healthy?

Tanganyika chiclids want very clean water with low nitrates. I also want to do less water changes, 25% every 2 weeks. It's a marine tank converted to tropical so just using equipment I have available. If i can keep it stable at around nitrate 5-10 ppm then I'm happy and would have thought there was enough for the plants I have to grow.

 

[Yo-han]

Epipremnum is what I used ones. Grows really fast!

 

[dw1305]

Hi all,

So what you're saying is that CO2 is not a issue or limiting factor in my situation due to other restricting factors?

Yes.

If so, it's pointless for me to supply any Co2 and might as well just go with very low light or lower it until the plants stop de-calcification (or at to a point were it doesn't look too bad).

I don't think you can really stop de-calcification, or that it is a good idea trying, if your water is suitable, de-calcification will occur. You would be best to supply reasonably high light, as you want a growth of "aufwuchs" for your Eretmodus.

If you think of it in terms of ORP (oxidative reductive potential) or REDOX, you have fish from a high oxygen, alkaline environment where most elements are bound as phosphates, hydroxides or carbonates, and are unavailable to the plant. The same applies to CO2, it is always naturally going to be in very short supply, because of the CO2~HCO3- equilibrium and reserve of dKH buffering.

I am a bit confused! why would you want to reduce the Nitrate levels? Virtually all of us on the forum feed our plants so they grow healthy?

Tanganyika chiclids want very clean water with low nitrates.

OK that helps a bit. Nitrate itself has very low toxicity to fish, even sensitive ones like Tanganyika cichlids, this means that the 30ppm NO3- you might add from the dissolution of KNO3 isn't toxic. When the traditional literature talks about "sensitivity to nitrates", what it really means is that high nitrate levels are the "smoking gun" from the nitrification of ammonia (NH3) and nitrite (NO2-). In a non-planted system NO3 will accumulate, unless it is removed by water changes, or out-gassed by anaerobic de-nitrification. In planted systems, with reasonable plant growth, NO3 levels will normally fall to 5 - 10ppm NO3. Because actually measuring NO3- levels is problematic in anion rich water, we have to use plant growth and health as a proxy for NO3 levels.

cheers Darrel

 

[dw1305]

Hi all,

Epipremnum is what I used ones. Grows really fast!

It is a good one, quite a few people use this:
<pothos | UK Aquatic Plant Society>
cheers Darrel