Plants melting question?

So I've had my 29g High tech planted tank up and running now for maybe 6 months and all the plants have been growing amazing, even Dowoni (for a short time) and then a few plants started to melt.  There are a LOT of plants in there so I'm not going to list them all but the ferns, fissidens, anubias, subwassertang,moss, rotala(s), marsilea minuta have remained fine...what is melting is, Pogostemon erectus and helferi (aka:dowoni), Linernia rotundifolia, Staurogyne repens, ludwigia.

The first plant to start to die back was the most fragile (and thus I didn't think anything about it) and that was the Dowoni, then all at once (that's how it always seems) the other Pogostemon the erectus has almost completely melted.  The repens could be from my "hill" falling down over the plant continually covering it up and its trying to come back, I can see if poking through.

So I do weekly water change (scouts honor) and for ferts I use Osmocote Plus under the Safe-T-Sorb clay substate.  I also does weekly excel, flourish, and now equilbibrium (that was for the Dowoni).  The lights are 2x25w CFL's 6,500 and 2x15w CFL's 6,500.  I would think if it was the lights then the plant wouldn't have started growing great ( I trimmed the erectus many times).  So i'm confused what's going on?

Is it PH, light, the Co2 is also fine and my drop checker in my tank shows lime green (now that i'm saying this should I be changing my solution for the drop checker more often? I only changed it once about 4 months or more ago.)

Anyway, any thoughts or idea's would be appreciated.  My other planted tanks are doing fine!

Cheers!  

Hi BallardFishGuy,

Have you checked any of the water parameters (PH, dKH, dGH) lately and compared them to when the tank was doing well?

Here is something to consider. As the tank continued to do better and better and the plants grew and grew did you increase your fertilizer dosing? Obviously with more plants more nutrients are needed.

I have not used Osmocote but I understand it to be a good substrate fertilizer but it's release of nutrients is dependent on temperature....the higher the temperature the more the little balls release. According to what I have read Osmocote lasts 8-9 months at 70°F; less time at higher temperatures. It is quite possible if you have not replenished what you put in initially that the tank is running out of nutrients. It sounds like you could be running into a nitrate deficiency.

Hope this helps!
-Roy

Thanks Roy, I just posted on Airstone too! You have brought up several good points and knowing how great your plants and tanks always look I need to investigate more.

I will check PH with my kit and see where it sits. As for dKH/dGH doesn't my drop checker (if working properly) check that? If not how should I do that? Man I feel like a rookie here!

And I didn't know that about the Osmocote and the temp, my tank is at 76 usually. And it's been around 6 months. WHen I started with it I went with someones recommendation (maybe on Airstone) that I should use a little pinch per 6'' or so...I went on the conservative side if I think about it now.

Hi BallardFishGuy,

Saw your post on 'airstone' but figured responded here so I will follow up here. Thank you for the kind words about my tanks!

The Drop Checker with 4.0 dKH water and indicator solution will give you your CO2 concentration. Your carbonate hardness (dKH) and your General Hardness (dGH) have to be tested with test kits. Since you are close to The Fish Store maybe take a water sample there, ask them to check your dKH, dGH, and your Nitrates. Without any water parameters my best guess is your poor plants are starving. Maybe pick up a small bottle of Seachem Flourish Comprehensive, dose your tank for a week per the instructions and see if there is improvement.

Thanks Roy, I will drop by the fish store for the dKH and dGH test. I can test for Nitrates, I have a test kit but it's the classic, PH, High PH, Nitrates, Nitrites, Ammonia kit.

I will look at getting some Comprehensive as well!

The strangest thing that some plants are still growing strong while others are not. Maybe that is because of the level of hardiness/requirements of each plant? It would make since my largest plant in the tank is my java fern and it's HUGE by far the biggest...could it be starving the other plants?

Hi BallardFishGuy,

My experience has been that different plants require different levels of nutrients. Possibly the plants that are still growing are the ones that don't require a high level of nutrients and the ones that melted needed the higher level?

I feel like that might be a ph issue. Or temperature

Update:

I tested the water (which I changed last Friday) and it's PH is at a reading of around 6.6 - 6.8 and the Nitrates are zero.

Temp is always steady at 76 and the drop checker is still reading a nice lime green color.

I also trimmed back the dying plants and moved a couple around and also added more osmocote...not a lot but a few around the tank. I still think i'll see what my water hardness is tomorrow.

I've had wide spread plant death due to swings in my ph. When I've been using co2 because my tanks are not buffered very well. My ph would yoyo before and after the co2 came on.

hobbyorobsession wrote:I've had wide spread plant death due to swings in my ph. When I've been using co2 because my tanks are not buffered very well. My ph would yoyo before and after the co2 came on.

How did you overcome that?

Added crushed coral In my filter to up my water hardness

Yeah that's what I did, I added crushed sea shells in a bag to my fluval basket. That reminds me I need to clean the filter. Last time I did I found about 6 RCS babies living down there!

For me some plants will melt when I move them. Most recently it was a big healthy Crypt and a mother Lilly (it was huge). I transplanted them & they both died down to nubs. Granted I didn't not acclimate these plants so I would totally understand shock from parameter shift.