Hi all

I have had my planted EI dosed tank set up for around a month now and all my plants seem to be doing pretty well, except for my Hygro cormbosa angustifolia and Hygro polsperma.

My cormbosa seems to be the worse off of the two with semi transparent leaves where the veins can clearly be seen and pinholes in the leaves which develop into larger holes with the surrounding leaf dieing back too. My polsperma has similar problems however it seems to be affected to a lesser extent. I am unsure whether the problem could be due to pests, something I am lacking in my dosing schedule, or another factor.

My CO2 is around 25-30ppm which I am still tweaking, the light is on for 10h a day, I dose 1.5ppm KH2PO4 and 7.5ppm KNO3 every other day, Epsom salts 1/3 teaspoon 1 week, trace TMG 5ml every other day for my 120l, 3.5w tank. Tap water and latest test results of tank water below. I am currently still changing the water a couple of times a week and have activated carbon in the filter, however the water I put back into the tank is quite cold and I wondered if this could possibly have something to do with it.

I have also have noticed I have a few snails in the tank, which I am removing as I find and what appears to be a little brown mite of some kind on the damaged leaves. I have also recently added some Malaysian trumpet snails to the tank however I encountered theses problems before I put them in the tank.

Any suggestions welcomed
Regards.

Tank water today, light on 6h,
Dosed KH2P04, KNO3, Last water change sun.
PH- 7.0
NO2- 0.1
NO3- 5
NH3- 0
GH- 14
KH- 8
P04- 1.0
CA- 100ppm
FE- 0


Tap water
PH- 7.5
NO3- 5
PO4- 0
KH- 12
GH- 20

If you are supplying 10 hours a day of light that is enough; if you are supplying 6 hours worth a day that might not be enough for a light lover like hygro "angustifolia". H. polysperma also seems to prefer a lot of light, although it will live with a lot less than you are providing.

You might consider increasing the nitrate dosing. An average level of 5 ppm isn't very much for a tank with 3.5 watts per gallon. Some people suggest 10 to 20 PPM, or more.

Good luck!

Bill

Hi kitty,

Firstly, how are you measuring CO2 and what lighting do you have?
Secondly, if your tests are correct (any many test kits aren't that good) you are showing Fe=0.
What you have sounds a little like a K or FE shortage. However, with what you're dosing it doesn't appear to be, so I would say CO2. You could also do with more KNO3.
Are you sure of your CO2? Do you have a drop checker to measure it or are you relying on pH/CO2/KH tables?
Try increasing it slowly over the next few days, watch the fish in case they start heading for the surface gasping.

Also, your tap water going in is quite hard, you're dosing Epsom salts yet you have tank reading a third less?

The little brown dots on the leaves may well be snail eggs or a few diatoms.

Hi aquabillpers and Bhornsey

I am supplying 10h of light a day; 6h was just how long the light had been on when I carried out the tests on the water. My KN03 dosing is 7.5ppm every other day, would you suggest increasing this as my tank is quite heavily planted.

I am measuring my CO2 through the use of a drop checker, I recently tried turning up my CO2 however I managed to turn it up too high and lost some of my fish while I was at work, so I am slowly turning it up at the moment until I find the middle ground (however I experienced the problems with my Hygros before this.) I have the CO2 coming on a couple of hours before the light, however I find my plants don’t really start pealing until the end of the day, and my ricca appears not to pearl at all.

I believe the lower GH in my tank water may be due to the fact I am only dosing Epsom salts 1 week and doing water changes 2 a week, would you suggest dosing more often? Also I have ADA aqua soil in my tank and bogwood which I heard can lower the GH.

My lighting is 2x 36w Interpet daylight plus and 2x 24w Interpet triplus in an over tank light, giving me a total of 3.5w. I have retaken my FE test a few time and always seem to get the same result 0, so I am unsure of these results are accurate or not.


Thanks for your time
Regards.

You need to be careful and slowly add more CO2, do so only when you are around and can observe.

Make sure you have good surface movement also.
The plants have no light or nutrient issues, they have access to the water and the sediments.

So all that is left for these two weeds is CO2.

Regards,
Tom Barr

Not to be disputatious, but I have a huge growth of H. polysperma in a 2 WPG tank (prox) with a soil substrate. There is no carbon augmentation. There is some nitrate dosing. The plant needs substantial trimming every 2 weeks.

Excepting this tank, I have never been able to get that plant to grow as well as well as it seems to grow for others.

It could be a CO2 problem, but in my case I think it has to do with bad karma, which has been mitigated in the case of my latest tank.

Bad karma and/or insufficient CO2 can explain a lot of complex plant problems.

Bill

Hi Tom and Aquabillpers

Thanks for your replies. The worst off of my Hygros seem to be those planted next to the intake valve of my filter, is it possible with them being at the furthest point from the outtake flow of my filter, that they are not getting the same supply of nutrients, could the intake valve be taking nutrients away form them before they get a chance to absorb them?

I am running my CO2 into my external filter too, could this be affecting the growth rate if they are furthest away from the filter flow and CO2, or would the fact the CO2 is being absorbed in the filter make no difference to this?

Would you suggest that I carry on with the water changes 2 a week with the dieing plant matter I am getting, can I risk starting to slacken off to 1 a week instead?

Perhaps Aquabillpers I also share your problems of bad karma as I have always struggled to grow stem plants, or maybe you have passed your bad karma on to me, either way at least it takes off some of the blame on me!

Passing on bad karma is a great way to make things better.

A while back someone did that to Tom and since then he has had very little success in growing fresh water algae, no matter how hard he tries.

Bill

No reason why the non CO2 approach should have that expression, however, your plants and tank is adapted to low CO2, this tank is not..................

That makes a huge difference in growth and expression.

As well as advice given.
I can grow most hygros very well in non CO2 systems, with or without sediment nutrients sources.

But this is not a non CO2 system.

Regards,
Tom Barr

No, I can induce them when I see fit, and every so often when lazy, when I do not.
But it's the same old routine to get rid of them.
Over and over and over again.

FYI, plants can and do adapt to low CO2. They have far more Rubisco ready to snatch the low CO2. So when you scale up and add more CO2, they do well and there is no algae issues. After sometime passes, say 1-2 weeks, they reduce the Rubisco, they do not need much when you have 10X the CO2, so they downregulate that.


Now, reverse that senario. What happens when you go from a high CO2 situation, with a plant that have reduced the rubisco down a great deal, then reduce the CO2 supply suddenly?

Algae, poor growth, severe CO2 limitation. After 1-2 weeks, the plant can adapt.

But what happens if your CO2 gas injection ppm's are all over the place?
Bobbing between high and low levels?

The plants cannot adapt to both quickly, and they have lots of trouble, some grow okay and in spurts when there is enough cO2, but algae takes over fairly quick.

CO2 levels can change in minutes to about 1 hour, Rubisco levels take much longer to adapt assuming they have enough other resources, about 1 week or more in some cases.

When that occurs, the plant also reduces and downregulates NH4/PO4/NO3 uptake as well.

Regards,
Tom Barr