Originally Posted by Nemo the Clownfish
My plants have all stopped growing and my Sword is turning brown on the tips and edges of the leaves. I dosed the tank with 15 mg/L of K2SO4 (Potassium) last week. Maybe a little bit of growth. I think maybe I need to dose Phosphate. I am using Flourish Comprehensive, as well as Equilibrium.
10 gallon tank, started 4/18/2012.
Lighting: 1 CFL 13w 6500K
Photoperiod 6 hours
Substrate big gravel :(
Now that I think of it, I may need to add another bulb, which will be a 10w CFL 6500 that I have, or probably two 10s.
I don't know about the light, I'm into LEDs. I run 14 hour periods too... not comparable I guess.
The KH looks low, is that the level that you bring it up to with Equilibrium? I'd suggest higher, maybe up to 4 or 5 and see how they do.
Have you been dosing potassium and phosphate all along? Given the plant load I wouldn't expect that you would need to if the KH were higher and I suspect, but don't know, that spot dosing like that may be either more harm than good or just not useful unless all nutrients and light are up as well.
I looked at your tank, nice looking. I can't tell how much surface disturbance you have but be sure that there isn't much as that will off gas CO2. The plants produce enough O2 that letting the CO2 increase naturally can help without affecting the fish.
Those are some ideas for thought if nothing else... I haven't had to deal with plant issues... other than some growing too fast, so I haven't actually had to do anything other than turn my lights on and off and add some flourish comp once a week.
Sidenote: I have a plant only experimental tank going. the KH started out at 20dKH and was down to 8dKH whereas the GH did not drop as much relative to the 23dGH starting pont... down to 15dGH. The plants use the KH components (calcium carbonate CaCO3) and some of the GH, to a lesser degree. That is why I am suggesting to raise the KH. I am anticipating a point where the plants will not be able to lower the KH any further and I expect to see it around the 4dKH mark.
Sidenote 2: Looking at the Equilibrium ingredients of K20, Ca, Mg, Fe and Mn only, I might suggest some limestone (Dolomite) or crushed shell material to bring up the CaCO3 levels.