Fert Dosage For Low Light Tank?

[Riso-chan]

I think I've been over dosing my tank with liquid ferts since my lighting is low and the plants can't soak up the stuff quickly enough. How do I know this? Well, I've had an occurrance of green hair-algea on the sides of my tank and a little on the plants. Had to manually remove it, luckily, it wasn't so much that it would cause great worry.

My Ferts:
Flourish(traces)
Flourish Excel
Flourish Potassium

My plants:
ruffled amazon sword
java ferns
java moss
crypt. wendittii
hornwart
& watersprite(soon to be added)

I have 80 watts over my 55 gallon

Would dosing everything once a week be better than 2-3 times weekly?
Open to any suggestions, though my lighting must stay low for the time being. Thanx~Angela

[Captain Hook]

It could be from a nitrogen (N) defiency

[RTR]

Or a phosphate deficiency. Nutrients need to be in balance with each other and the plants and lighting

[beviking]

I would stick with dosing twice a week in your situation unless there are so many plants the fish have little swimming room. Of course, knowing your N and P would be very helpful. I dose "the gammut" and the first thing to run out is P.

My suggestion would be to dose 2X a week and get those test kits (N & P) if you haven't already.

[Riso-chan]

I don't have tests for N or P. However, my nitrates have stabilized at 10ppm if that has anything to do with it. I use tapwater, and I think we have a certain amount of phosphates in their.

The other thing is that Flourish contains amounts of both:
N...0.07%
Available Phosphate...0.01%

Just keep dosing 2x a week for each fert?

[Captain Hook]

What kind of water change schedule do you have?

My guess would be that you are overdosing fertilizer which is causing algae. With that low level of light you probably don't need to add too much in the way of nutrients.

[Riso-chan]

I typically change out 5-10 gallons every other week. I add ferts with the change usually, and during the week too.

[RTR]

The quantity of nitrogen and phosphate in Flourish is trivial.

[reiverix]

N & P test kits are a must for planted tanks IMO, not a luxury item.

[djlen]

I agree with the above remarks and would add that guessing at tap water parameters is not the best way to deal with your tank's makeup. Since it is your source, you should know what it's giving you of P and N especially. How you know that your N has 'stabilized' without a test kit is difficult for me to figure out.
Don't even count the N and P you get from Flourish. As RTR says, it's trivial. Flourish is for traces only and should be counted on only for them.
Since you are dosing K you need to balance that with N and P. For your purposes I would suggest Flourish Nitrogen for the N and Fleet's for the P(because it's cheaper and just as easy to dose).
My impression, based on your tank stats and what I've read here, is that you have a relatively light plant mass. So that in addition to your relatively low light would lead me to suggest that you cut your K dose by 1/2, add Nitrogen @ 1/2 the recommended dosage on the bottle, and dose 4 drops of Fleets after water change. I would count the number of mls. you are dosing of Flourish currently, divide it by 6 and dose that quantity of mls. daily, skipping water change day, for traces.
You want just enough nutrients to supplement your fish waste a bit, but you don't need a ton since you're not using CO2 and have moderate light.
You should also find out, if unknown, what your gH and kH of your water are because it may be a good idea to supplement addition Ca and Mg depending on your findings.

Len

[Riso-chan]

I understand, I'll have to find those tests. My plant mass is light I guess, but I'm shooting for the goal of a dense mass of low-lights. Soon...:) My large java fern is growning a little baby on its leaf right now, and I have a few other little babies in the tank as well. The crypts are spreading slowing to cover the gravel, and the hornwart is constantly trying to overtake the top of the tank. I'll check around for the needed items, thanx~Angela

Edit:
found the ferts at Drs Foster & Smith, My kh/gh are likely very high, because the water in this area is very hard. I'm going to find out if my lfs knows anything about the NPK values of this area's water.

[djlen]

While you're there, take a sample of your tap water and have them check it for N, P, gH, and kH. Any worthwhile LFS will do this service as a matter of course.
Sounds like you are on the right track. Just balance things out, keep the nutrients light, and you should be good to go.:)

Len