Red plants turning yellow

[alexraven]

This is my 1st post in here,so hi everybody and..Merry Xmas !!
I have a 79G planted tank. It is running almost 3 months now and most of the plants are going great. Still, some of my red plants are yellowish in their appearance and the reason is a mystery to me, so I thought maybe you could help me on that ! To be exact the plants wich are whitish are: Proserpinaca palustris, Ludwigia repens, Eusteralis stellata and Rotala macrandra.

I will give you as much informations as I can :
Lighting :216W, 4x54watts , T5,Sylvania gro-lux.
Photoperiod: 11h 2X54 and 3h 4X54
CO2: 3b/sec at ext. filter input
PH 6.8
KH 7
DH 9 (I am using plain tap water)
NO3 10-15ppm
PO4 0.5-1
Livestock: 20 Harlequin rasbora, 10 Threadfin rainbows,5 CPDs and 8 Yamato shrimps.

I am dosing 5ml IRON every day , 5ml Seachem TRACE 3 times a week and 5ml POTASSIUM every day. I believe this is a havy dosing but still my plants are yellow! As a result some algae started to appear the last 2 weeks, it looks like Spirogyra or green thread algae ??
Also I have difficulty and find it challenging to keep my Myriophyllum tuberculatum healthy and it has stunned lately..
Some photos of my tank and my plants may help:
Thank you in advance .

 

[VaughnH]

You have a very high light intensity, especially during the noon burst period. But, you aren't providing the quantities of nutrients needed to support the growth that light is driving. First: you can't rely on a specific number of bubbles per second of CO2 to give an adequate concentration of CO2 in the water. If you buy or make a little drop checker, fill it with 4 dKH distilled water and pH reagent, put it in the tank, and in about 2 hours it should be green to yellow green if you have enough CO2 or close to enough. This is only a way to get close to the right amount - final adjustments to the bubble rate may be needed, while observing for fish distress and plant pearling.

Second, you can't depend on test kits to determine how you fertilize, unless you calibrate the kits using standards of known concentration. Much easier, and very effective is to use the Estimative Index method of dosing. You can buy dry agricultural grade chemicals, KNO3 and KH2PO4 from several different webstores, very cheaply, and have the best known fertilizers for macro nutrients.

Finally, to be sure all of those nutrients, but especially the CO2 is available to all of the plants, you need good water circulation in the tank, so all of the plant leafs are swaying gently in the current. A Koralia or similar type powerhead is one way to get that.

That is a very good aquascape, too! It is well worth the effort to get it growing in good health, just to keep that aquascape looking its best.

 

[alexraven]

Thank you 4 the quick reply. I have now some extra questions..
1. You are saying that my light is too much but i need a good growth since i dont have extra tanks to grow plants and sometimes I have to start with just a little piece of a plant and make it fill a whole area. Also in plant databases, informations about plants like R.macrandra and M.tuberculatum are saying that one needs to have intense light to grow these plants.Isnt that true?

2. I had trouble monitoring CO2 and as a result I got algae problems. Now I am not depending on bub/sec but as you said I am adjusting CO2 by watching close pearling/fish distress. There is a lot of pearling during the burst period and 3-4 hours after it. I count CO2 levels till now by measuring PH/KH but a drop checker is going to be a handful addition. And since I dont know how to make it I will buy one.

3.As 4 good circulation I forgot to mention that i have 2 external filters Eheim 2236 and Eheim 2215, plus a 1000L/h powerhead. I also forgot to mention I am doing 50% water changes every week and cleanig my filters the same day. Is this too much? I do trimming another day not to shock my system too much.

4. Your suggestion about using EI method is a good one and it has crossed my mind lately . I have to read about that and learn how to use dry fertilizers. It is very expensive to buy all these Seachem products. But I have been warned by friends in a greek forum that the dry fertilizers will perhaps make my water harder. Is this true?

5. As 4 macronutrients am I ok or should I increase NO3/PO4 ?
CO2 levels are at optimum range now. What about the micronutrients? Clearly my red plants show some kind of micro deficiency but how is this possibile with 5ml iron every day? do you think I will have to increase Iron and traces ?

Thanx for helping me out , my experience in planted tanks is 1 year only and this is my first true aquascape.
I know I ask many questions but its the only way to learn ad understand more,besides reading.

 

[VaughnH]

1. I don't say you have too much light, just that for the amount of light you have you need to be supplying non-limiting dosages of all of the needed nutrients. With the high intensity light that you are using, that requires fertilizing with nitrogen, potassium, phosphorous, carbon and trace elements, all in adequat quantities. And, the easiest and simplest way to do that is by using the Estimative Index method of dosing.

2. With the good pearling you are getting you may have enough CO2, but I find it to be very reassuring to see a green to yellow green drop checker in the tank to prove that I am at least close to the right amount.

3. You have enough pumping capacity to get good circulation, but do you have the water surface rippled? Look at the photos here, http://www.barrreport.com/general-plant-topics/5085-how-much-surface-ripple.html, to see what good water surface rippling looks like. I get mine by pointing my powerhead, which is mounted high in the tank, at an angle towards the surface.

4. Using dry potassium nitrate and mono potassium phosphate will not increase the hardness of the water. It takes mostly calcium or magnesium to increase the GH, and a carbonate compound to increase the KH.

5. If you haven't calibrated your test kits you can't be sure how much nitrate or phoshate you have in the water, just by testing. But, if you dose those per the Estimative Index method, you can be sure you have enough. Red plants are not an indication of having enough iron or other traces. Most red plants are red because it is the normal color for them, and if they are growing well they will be red. The best way I know of to be sure they will be growing well is to follow the Estimative Index method for fertilizing, and maintain good high levels of CO2 in the water. Pearling is one indication that the plants are doing well, but not necessarily as well as they should do.

 

[alexraven]

You have been a great help to me with your answers. Many things are clear to me now. I will follow your advice and start dosing with the E.I. method.
Yes I read the thread about water circulation and I also have had problems with oily surface some weeks ago. Now I have the outputs of the filters towards the surface and it is much better.
The only thing I do not understand is

If you haven't calibrated your test kits you can't be sure how much nitrate or phoshate you have in the water, just by testing. But, if you dose those per the Estimative Index method, you can be sure you have enough. Red plants are not an indication of having enough iron or other traces.

You mean that If one uses the E.I.method, there is no need of doing tests anymore?

 

[VaughnH]

The only thing I do not understand is
You mean that If one uses the E.I.method, there is no need of doing tests anymore?

EI is designed to maintain non-limiting concentrations of all of the needed nutrients in the water, just by doing somewhat excessive dosing of all of them on a routine basis, then changing about half of the tank's water once a week to remove any excess nutrients. No testing needed or even very useful. You can always modify the EI dosage schedule to better fit your tank conditions, and if you wish you can do some testing to help with that. But, if you don't calibrate the test kits first, the testing will be of no value.