[Cory_guy]

I had this tank (90 gal. planted) for over a year. All was going great but last couple of months my plants started slowly dying. I am not sure why but they are just not what they used to be. I replaced lights, I have not changed any fertilizers, I kept the same everything because they worked great in the past (Flourish – CO2, iron, trace, comprehensive). The only thing that I noticed was that hardness and PH have slowly crept up. PH – 7.5 GH – 120 KH – 180. Everything else is in order (Ammonia -0, Nitrate – 0, Nitrite – 0). Fish are doing great but I care for my plants more.
Can PH, GH and KH be the reason for my problems? Or am I missing something. Most of my research says that plants should be ok with this, but I could use any lead at this point. HELP!!!

 

[gy960]

How are the plants dying? A few pics would be great.
And Nitrates-0 !?

 

[Jadelin]

Yeah, if you're using CO2 without adding KNO3 and your nitrates are zero, it looks like your plants are using all the nitrates available and are starving for that (and maybe some other things).

 

[Cory_guy]

I attached couple pictures. How can I add KNO3. Do i need to increase comprehensive supliments or is there another one I need to start addin. WHat should the readings of Nitrates be?

 

[Jadelin]

Can you give us a little more information about your tank?
What type and how many lights do you have?
How long are they on for?
Has anything changed about your lights recently?
Has anything about your fish load changed recently?
It looks like you're using gravel for your substrate, right?

It's a little interesting that everything has been good for a year and now is starting to decline, which is why I wonder if anything has changed.

So it looks like you're adding all these things from the Flourish line; Trace, Iron, Comprehensive, yes? If you are dosing all of those, your plants are getting all the type of nutrients they need, but probably not enough and not likely in the right proportions.

You said CO2; do you mean you're dosing Excel, or that you're injecting CO2 gas?

I don't know how much you know about plant fertilizers, but I'll try to give a quick run down. Plants need 3 macronutrients in large amounts: Nitrogen (N), Potassium (K), and Phosphate (P). They also need small amounts of several micronutrients.

Comprehensive is supplying N P K and most of the essential micronutrients, but like I said probably not enough. If I were you I would keep dosing with your Flourish supplies until you use them up and look into dry fertilizers because they are exponentially less expensive.

You can buy dry fertilizers at sites like these: http://greenleafaquariums.com/aquarium-fertilizer.html, http://www.aquariumfertilizer.com/index.asp?Option1=cats&Edit=2&EditU=1&Regit=2

You'll need to get KNO3 (supplies N and K), KH2PO4 (supplies P and K), and a source for micronutrients (I use GH booster). In a planted tank ideal nitrate levels are 10-20 ppm.

How much you dose will depend on how high your light is.

I hope that helps more than it confuses, and feel free to ask questions.

Hopefully someone else might be able to see if they recognize the specific symptoms of your plants to confirm my hypothesis.

 

[Sharkfood]

For most plants, KH and pH don't matter at all (within reason).

 

[Cory_guy]

Hey Jadelin,

I appreciate the help.
Here is the info you asked for.
I have four 54 High Output Life-Glo T5 lights. I replaced those 3 weeks ago after the plants started to go down, thinking maybe that will help. It did not make a difference. They are on for 11 hours. NO fish change. Gravel for substrate.
I am dosing Excel indeed.
Thanks for the info on the fertilizer. I would love to look into the dry stuff, because you are right it is very expensive. I might need some help with getting the right mix, because it seems so complicated and I am new to all this. But I really want to have my plants do well! I have doubled the comprehensive supplement and I hope it will work.
Do you think I have enough lights? When I got my set up I started with 2 life-glo and 2 power – glo T5s. Do you think that was a better system? When I read about all the lights and stuff it does not really register with me. I guess I am a slow learner, but I really want to make it work.
Thank you for all your help I really appreciate that.

 

[Jadelin]

By replace the lights do you mean that you got new bulbs, or that you got a new fixture? Because that is A LOT of light! I'm amazed that you don't have algae problems with that much light and that long of a photoperiod. I would recommend only having two lights on at a time if your fixture will allow that, or raising it about a foot above the top of your tank. Average photoperiod is usually around 8-10 hours. If you start getting algae problems I would definitely consider making some of these changes.

With that much light you could follow the estimative index (EI) method of dosing. There is a thread about it here: http://www.plantedtank.net/forums/fertilizers-water-parameters/21944-_dosing-regimes_.html They don't have exact amounts for a tank the size of yours, but you could extrapolate out from the examples given. I would say your plants are definitely using up all the available nutrients with that much light, and they also are probably needing more carbon than they can get from just excel. Unless you want to add injected CO2 and make it a high-tech tank (which many people do) I would definitely recommend cutting back on your lighting.

Don't worry, when I first started learning about all this I avoided fertilizers and lights because they just seemed so complicated (also, I prefer low light tanks since they have less maintenance). Keep asking questions and eventually you'll get your head around it.

 

[Cory_guy]

Thanks again.
When i say replacing light i mean replacing the bulbs yo uare right.
So I doubled the furtilizer and cut an hour of a light time. I hope it will help. I will keep monitoring, and if that was the problem I will swtch to the cheeper firtilizer because this is killing me. THANK YOU AGAIN!!!