[Avalon]

I've been growing plants for a long time now and this is the only plant that has ever given me fits and is still giving me fits! It's stunting like crazy. Actually, half of the stems are stunting, the other half have smaller new growth. What am I doing wrong? All of my other plants are doing ok. What gives?

Tank: 29g
Lighting: 2x65w 6700K Coralife fixture
Carbon: pressurized CO2 and Excel
Nutrients: 7-8 ppm KNO3 eod, 1.5-2.0 ppm PO4 eod, 10 ppm K2SO4 eod, 12 mL Tropica PNL eod, Flourish Iron 2 mL daily (eod = every other day)
Substrate: ADA Aquasoil /w Powersand + Tourmaline BC
Water: 75% or better RO, the rest is tap. I know the KH is really low, the pH is very low, and I don't have a reliable method of testing the GH.

I've never had a growth problem before with this similar setup (substrate and 100% RO water), so I'm doubting the GH as being an issue. I also doubt it because my other plants (Toninas, various rotalas, etc) are doing well. What is it with this plant?

 

[Cavan Allen]

Are you sure the nutrient levels are really what you say they are? More may be needed.

I would dig a bit deeper into your GH. Calcium to Magnesium ratio is a possibility.

You might consider splitting up your dosing to every day if nothing else works. Some plants really seem to appreciate a steady nutrient supply and that's definitely one of them.

 

[BryceM]

Yeah, it's a finicky one. Mine would do well for a while and then stunt again. After a week or two of that, zoom, it would start growing again. When it would grow it was almost a nuisance weed, needing a trim every week or so. My experience was the same as yours. Toninas & all the rotalas do fine and the stellatus just was never perfect.

My solution was to give up and switch to Pogostemon stellatus sp. 'Broad Leaf' which is much friendlier. You better have a big tank to house this monster in though. Each plant can be 6-8" in diameter when growing well.

You seem to be adding lots of nitrogen, which can be an issue in softer water (despite what Barr says). I typically dose about 6 ppm per week. That keeps the NO3 around 10 ppm in the water column with 20% every other day water changes. The Ca/Mg ratio can factor in too and your potassium addition might be a bit on the high side.

 

[Cavan Allen]

I second the potassium comment. I find adding it (aside from the other ferts) is often not necessary.

 

[Brilliant]

Thats so strange. Ive grown three types of this plant, a broad leaf with lighter green color that looks like Limnophila aromatica, a broad leaf with pink color and the thin leaf. The only time Ive had stunting is when co2 is off, typically after canister swap or something.

Ive actually found potassium to be a staple and sometimes the only fertilizer I use. Next to iron I think its one of the most important water column ferts.

With the spiteful comment you begin to wonder.

 

[BryceM]

With the spiteful comment...

????

What was spiteful?

Brilliant, what is your water chemistry like? GH/KH? I'm not suggesting that adding K isn't necessary, just that you're probably getting enough from the KNO3 and KH2PO4. IMO, stunting is often an inhibition from too much of something rather than a nutrient deficiency.

 

[Avalon]

I think I'll try adding some Ca/Mg. I have some Barr's GH builder. Anyone know how much to dose to achieve adequate levels and how often it should be dosed? If I do that, I'll go to 100% RO since the municipal water supply here varies. I'll also back off on the N and K as well. Judging from the slight green algae, I'm still adding too much N, so I've almost got the dosing amount dialed in correctly.

I'll try that and see what happens.

 

[MatPat]

I think I'll try adding some Ca/Mg. I have some Barr's GH builder. Anyone know how much to dose to achieve adequate levels and how often it should be dosed? If I do that, I'll go to 100% RO since the municipal water supply here varies. I'll also back off on the N and K as well. Judging from the slight green algae, I'm still adding too much N, so I've almost got the dosing amount dialed in correctly.

I'll try that and see what happens.

I believe Barr's GH Booster was formulated to be dosed in the same way as Seachem's Equilibrium.

P. stellatus grew well for me in Maryland as long as I kept on top of my CO2. In MD my GH was 4 dGH (no idea of the Ca:Mg ratio) and KH was 7 dKH. Everytime it would stunt, I had a CO2 issue, caused by low flow from my Magnum, which I used as a CO2 reactor. I have not been able to grow P. stellatus worn a darn since moving to Dayton. The GH here is 14+ and KH seems to be around 9dKH depending on the time of year. Ca to Mg ratio here is about 1:3 (28ppm Ca and 79ppm Mg). I can't grow a lot of the plants I used to grow and believe that is due to my Ca:Mg ratio. One of these days I will make the swap to RO water but that is a ton of water to make for water changes on a 75g tank

 

[jeff5614]

FWIW, I'm having problems with it too. It grows great for a while and then it's like it almost dies back for a while. My water is very soft and I dose EI including adding Equilibrium. CO2 is approx 30 ppm based on the drop checker.

It was doing well until I topped it 3 weeks ago. I replanted the tops and tossed the bottoms. Now it's just sitting there looking unhealthy - hardly growing and kinda pale in comparison to before.

 

[jeff5614]

Here's a post on Tom Barr's site that may or may not be helpful but it's the same topic.

http://www.barrreport.com/general-plant-topics/4346-pogostemon-stellata-care-growth.html

 

[Robert Hudson]

The issue I hear the most often with this plant from probably three or four dozen of my customers is the plant turning green from red and not going back to red, or starting green and never turning red. Is this an issue you have seen Avalon, and is it all tied together with growth issues?

The potted plants that I recently got from FAN are completely green without a trace of red, but very full leaf growth. The most dense leaf growth I have ever seen on this plant. Their bare root bunches however have less dense leaf growth and are solid purple red. Same plant, same grower, but grown under different methods, both in mass production.

 

[BryceM]

I think the color issue is mostly a function of how much light it gets. I was able to keep this plant in a medium-light tank but it grew pretty leggy and didn't color up very well.

 

[Robert Hudson]

I don't know... I've had it under 5 watts per gallon and had it turn green. And the plants I have now that were grown hydroponicaly must have gotten a ton of light.

 

[Avalon]

I've been thinking again. I may go ahead and formulate a daily dosing plan since I haven't made any significant changes yet.

Robert: I have had some success with this plant in the past--just not for very long. When NO3 is high, it will be green. If you let NO3 get low, and I believe this is where daily dosing comes in, it will turn from green to yellow & purple. If micros and iron are high, it will take on a slight bronze hue and get a little more red (which is really neat when you see it). However, I've never seen this plant as red as in the plantfinder photos. I believe the rendition in those photos to be camera 'magic' and the Kelvin rating of aquarium bulbs being used (like 9325K bulbs for example). I'm not saying it's not possible...I just haven't ever seen it.

I think that to develop bushier growth, lighting and P levels should be high (2ppm~) and NO3 low but stable. As Tom Barr states, the plant is a very fast grower and can be almost annoying if the NO3 is high like in EI dosed tanks.

 

[houseofcards]

Interesting discussion. I've been dealing with a similiar issue with L. Aromatica for about three years.
When I first got this plant it grew like gangbusters coloring up nicely toward the top of my cf lit, EI-dosed, Eco-complete 72g tank. After around 6 months I noticed the great growth had stopped even though I was dosing the same amount. I tried all kinds of different dosing styles and nothing seemed to snap it out of it's frozen state. All new growth was tiny little leaves coming out of the trimmed tops. Eventually I started a new tank with AS about the same light and only dosing K and micros and the Aromatica took off once again, growing full and lush with nice color. But it was not to last, months later the plant started to stunt once again even after adding a light EI dosing schedule to complement the AS.

Certainly a mystery. Could it be that this plant has something in it's genome that prevents it from growing 12 months a year. In nature is it only seasonally submersed or partially emersed and when conditions change drastically it grows again, sort of the way it grows in a new tank. Just a thought.

 

[BryceM]

I don't know about the L. aromatica. I suspect you're seeing a deficiency of some sort. The biggest problem I have is that it grows too fast. I've never had an issue with it over a 2 year peroid ... at least not until I just said that. I half-expect to go home now and see it all melted.

 

[Avalon]

I'm beginning to think that I have too much light. I got to thinking about the daily dosing and the entire point of it (to maintain a stable supply of nutrients). Why not simply lessen the demand by reducing the light? I know for fact that most all plants still grow very well in low light conditions, especially when you have good CO2.

I've removed my current 2x65w fixture and just suspended a single 65w bulb w/ AHS reflector 4" above the tank. I think there's still quite a bit of light. Slowing things down should help greatly on all levels. I really don't care to prune plants twice a week anyway.

 

[BryceM]

CO2 and low-medium light is THE secret to happy 'scaping IMO. I have a 46g tank that is virtually maintenance free. I add NO ferts at all and there is no algae. None. It has spiral CF's in a DIY hood and gets a medium CO2 bubble-rate. It gets pruned once per 6-8 weeks and is arguably prettier than my mega-hyped-up 180 tank with MH lighting.

 

[Cavan Allen]

That may be true Bryce, but I think there are some plants that are really all or nothing. If they are, they're probably going to need everything maxed out. You can't shoehorn everything into a low maintenance tank.

 

[captain_bu]

The issue I hear the most often with this plant from probably three or four dozen of my customers is the plant turning green from red and not going back to red, or starting green and never turning red.

I have the broadleaf variety and it has been growing consistently well for me for about 6 months. Tank is 50 gallons, EI dosing with pressurized CO2, 2.6 wpg PC light. I have only been injecting CO2 for a little over 2 months, drop checker with 4 dKh water stays consistently on the yellow side of green. I was using Excel too up until about 2 weeks ago. When I didn't have the gas I was dosing 2x Excel daily and using a reduced rate of EI. With just the Excel the undersides of the leaves were very red, since starting CO2 the leaves have turned completely green. I have been using the same ratio of ferts as I was when the plant was red but increased the amounts due to the CO2. I would love to get the red color back but am not sure how. My formerly very pink Sunset Hygrophilia has also turned completely green. I did try cutting my KNO3 dose a bit but noticed a reduction in growth and plant vitality, when I upped it again everything in the tank grew and looked better.