Brown, dieing plants

[hashbaz]

My plants keep dieing. What is wrong?

 

[rich311k]

How much wpg do you have? What kinds of plants are you growing?

 

[hashbaz]

Just kidding. Here is a little info:

29 gallon
about 2wpg (ODNO)
EcoComplete

Ammonia: 0
nitrItes: 0
nitrAtes: 30-40ppm
gh 120ppm (6.7degrees)
ph: 7.0
kh: 80ppm (5 degrees)
CO2: 15ppm
Phosphates: ?????? (I assume they are high like the nitrAtes)

30% weekly water changes
Daily: ½ tsp Flourish Excel
twice a week: 3tsp Flourish Trace
twice a week: 3tsp Leaf Zone (3% K2O, 0.1% Fe)
(3tsp in 29 gal adds 4.1ppm K and .14ppm Fe)

plants: Amazon swords (1 lrg, 2 sml), several java ferns, 3 tiger lotus, 2 small wisterias and some dwarf saggitaria.

Plant symptoms: older leaves develop yellow spots, yellow tips and brown holes. New leaves seem fine.

Algae: a little green spot algae, and a lot fuzzy gray algae (about 3/16ths in long). I’m guessing that when I fix the problem with the plants, the algae growth will slow down.

CO2: I recently started a DIY CO2 system. I only have about 2wpg and dose Excel, so I am assuming that 15ppm CO2 is plenty.

I’m guessing that I have a Potassium deficiency. I add Leaf Zone which is Potassium and Iron. But I’m worried that adding enough Potassium will add too much Iron - Adding only 8.2ppm K adds .28ppm Fe.

I’m thinking of buying potassium sulfate from Greg Watson. But the budget is tight so I want to make sure that potassium is the problem before I spend my hard-earned money.

What do you guys think?

 

[hashbaz]

Rich311k, you were a little too quick for me. People often post questions without any background info, so I thought it would be fun to do the same but then reply with all the background info, but you beat me to it! lol

edit: I included a pic of the whole tank.

 

[rich311k]

LOL Looks like a K problem to me as well. I am looking forward to what the experts around here think.

 

[travis simonson]

Looking at your tank parameters I have to agree with Rich: the first thing that jumps out is lack of any potassium dosing. There are no reliable potassium test kits but low K levels often cause the exact symptoms you are experiencing, especially holes in leaves. You can buy some Seachem Potassium in the short run, but I would recommend getting potassium sulfate from www.gregwatson.com because it will last longer and cost considerably less. I would try dosing 5-20 ppm of K per week and see if your plants begin to improve. You might also want to consider a partial water change occassionally to bring down your NO3 levels. Ideally they should be in the 10-15 ppm range. Good luck

 

[azn_fishy55]

just a question that has something to do with this topic: What happens to your plants when your NO3 levels are below 10-15 ppm range, mine is 5 ppm.

 

[Hoovercat]

You won't really see effects from low N until it basically bottoms out at which point old growth will yellow as the plants move the N to continue new growth. The 10-15ppm level insures adequate available N to prevent this in tanks that might use 5-10ppm daily.

 

[BrianNY]

Just a comment here but I think knowing the phosphate level is important. This might be contributing to the algae prob.

 

[hashbaz]

I am hoping to get a phosphate test kit sometime soon. How many phosphates would one want, when the nitrates are so high? Does the 10:1 ratio still hold? 3 to 4 ppm phosphates seems a little high to me.

 

[czcz]

I agree that knowing PO4 is important: there is a school of thought that the green spot indicates PO4 limitation, but this indicator does not always hold true. If you do have a PO4 limitation it surely is helping the algae more than the plants.

Do not worry about the ratio if you have available, say 1.5ppm, PO4 with your 30-40ppm NO3. If your assumption of very high phosphates is correct, you should follow the advice of larger or more water changes to keep N and P at manageable levels, along with K dosing. (I think you should follow the advice regardless of PO4 measurement.) This will also allow you to drop back on Leaf Zone while meeting K requirement, as I am not too sure you need .28ppm Fe with your parameters, and larger pwc will likely give you what Flourish trace does. If you prefer your current water change schedule, how about adding some more fast growers to help uptake?

HTH