Swords turning brown. What's wrong? Also, can I remove fast growing stems now?

[Saver]

46 gallon tank
-Heavily planted
-96 watts (CF) for 9 hours
-Excel daily, 7.5ml (1.5x recommended dose)
-50% water change every other week
-Dosing consistently on M & F
-KNO3, 1/4 teaspoon, 2x a week
-KH2PO4, 1/8 teaspoon, 2x a week
-Traces, 1/16 teaspoon, 2x a week
-Tank running for about 6 weeks
-130ppm of "general hardness" (I don't know what that means exactly, but I tested it using my Taylor drop test.)
-No algae except for a little on the glass, no aglae eaters yet
-light fish load (10, 1" fish, tetras and rasbora's)
-PH 6.8
-Nitrates 10ppm on uncalibrated API test (but my tap water tests 0)

My melon sword has grown a lot, but the leaves are turning brown (new and old) and the old brown leaves are then becoming almost clear. I'd say 50% of this plant looks that way. Also my large (18"+) amazon sword has 2-3 leaves that are turning brown.

I have a wide variety of plants (dwarf sag, hornwort, water sprite, pennywort, kleiner bar sword, wisteria) and they all seem to be doing very well with the following excetion. My madagascar lace plant stays very small, which I image is due to not getting enough light (plants crowding it out.) The Egeria Densa is growing quickly, but there is a lot of space in between the stems from not enough light I guess.

I really need to trim the tank today. I'm waiting for my new tank to be delivered so I'll have some place to put my cuttings.


*What am I lacking in regards for the swords? They were healthy when I planted them. (CO2 is not an option, but removing the affected plants is.)

*Now that my tank is around 6 weeks old, can I remove the fast growing stems all at once and replace them with something slower growing without getting into much of an algae problem? (I don't care much for the swords, water sprite or hornwort which makes up 75% of the tank.)

Sorry for the long post. The UPS dude is pulling in with my new tank right now!

 

[VaughnH]

I have a 45 gallon tank, with 72 watts of AHS light. I dose 1/2 tsp KNO3 and 1/4 tsp or a bit less of KH2PO4 every other day, with 1/4 tsp or a bit less of CSM+B on the other days. So, I suspect you are underfertilizing by quite a bit. My experience was that I needed as much plant mass as I could get for longer than 6 weeks, too.

The major difference between our tanks is that I use pressurized CO2 instead of Excel, so my growth rates are probably a lot greater than yours. Considering that your fertilizing may be good. And, I switched from 96 watts to 72 watts of lighting to reduce my growth rates a bit.

 

[Saver]

Thanks for your reply.

I had posted back when I had just planted the tank and Tom also commented about me having too much light as well. Did you notice a reduced rate of growth when you changed lights?

You are dosing a good bit more than I am. I'll start changing the water every week and dosing 3 days (instead of 2) with the following:
-1/4tsp KNO3
-1/16tsp KH2PO4
-1/16tsp CSM-Plantex

That's half of the recommended EI dosage for a 40-60 gallon, but more than I was dosing before. Maybe I should dose more?

I'll just leave the fast growers there for awhile longer then. I'll just trim them back.

-Another question. I know we aren't suppose to dose KNO3 & KH2PO4 at the same we dose the traces. But, I've been dosing them the same day...just leaving 2-3 in between dosing. (I dissolve them in water first.) Could that be a problem?

Thanks for your help.

 

[VaughnH]

When I dropped my lighting from 96 watts to 72 watts nothing at all changed for about a month, then the plants gradually began growing slower. The plants that are right squarely beneath the bulbs still grow as if the lighting were more intense, but other plants don't. Why aren't you just dosing per the EI recommendations? The overdose, if it is one, will do no harm as long as you continue to do weekly 50% water changes, and then you can be sure the plants will not be short of ferts.

But, again, since you are not using CO2, just Excel, your plants may not be short anyway. Excel isn't equivalent to CO2 in it's effect on plant growth. One more point - Excel for a 45 gallon tank gets pretty expensive fast, especially with routine weekly water changes. So, you aren't saving a lot of money by not going to pressurized CO2. I can't remember anyone ever saying they regretted going to pressurized CO2.

 

[Saver]

Honestly, this is my first planted tank and it was so confusing in the beginning on what tank to buy, how much light the tank needed, what plants to buy, what fertilizers, how much fertilizer, how long to leave the lights on, and what fish to buy that are compatible together and won't eat plants. It took me a few weeks just to wrap my brain around cycling a tank....only to finally realize I didn't need to worry about it in a heavily planted tank. LOL There just isn't anyway I could've added another complicated thing, like CO2 equipment into the mix. Not to mention the cost of initially buying the tank and all...I didn't want the added cost of the CO2 stuff.

Excel isn't that expensive. I bought a 2L (2000ml's) jug from Dr. Smith's for $22. I dose 7.5ml daily which runs about .08/day and will last 266 days. So it will cost me about $28 a year. (That doesn't figure in the cost of shipping as I bought a bunch of other stuff at the time.) I don't dose any higher after water changes like the bottle says. (I don't understand doing a massive dose after water changes anyway. From what I've read, the Excel only stays available for 11 or so hours anyway. So why do a massive dose after a water change when I'm already adding a bunch of CO2 from my tap.) I just do a regular dose after a water change.

CO2 may happen one day. I'm just not ready to go there.