I have amazon swords in 2 of my tanks, and right now for some reason all my tanks have this horrible brown algae. Dont know if that is related so I thought Id mention it.

My plants just look kind of sickly. The new leaves turn a brownish yellow very soon after reaching their full size. I see people's aquariums whose plants have beatitful green leaves and no hints of yellow or brown, but all mine look like they are dying the minute they sprout. I still am getting new growth so I guess thats a good thing.

Could this just mean that there is not enough of the right nutrients in the water for them? I am a little uneasy about using fertilizer in a tank with fish. My nitrites are alway 20 because that is what comes out of the tap. I thought that would be sufficient for them but I guess not. Any advice?

I was having the same problem with my amazons when i wasnt adding enough fertilizer. Seemed like once I started using a good fertilizer the amazons started doing wonderfully. Clip off any dead or dying leaves, and make sure the roots are still white. If they start to turn brown and icky, take the plant out because its dying and will only add waste to the water. How many watts per gallon do you have in the tank?

Watts per gallon? OMG no clue. I have them in my 55 gallon tanks if that helps....the bulbs came with the hood...it was a kit....lemme have a look. The bulb says Eclipse Natural Daylight. And then some weird numbers that look like a code, but I cant read it..the printing is messed up. The light on this one is a natural white looking light.

My other 55 has a buld that says All Glass Aquarium 15 watt. This light looks more purple. It casts a purplish glow is the tank (which Im not to thrilled with), and I dont know if there is a differece between these two lights, but both tanks are having the same problem. Wierd but the hoods and lights are different on the tanks, but they were the same brand and I got them both at walmart, just different times lol.

I think the problem your having is you dont have enough watts per gallon. The bulbs those kits come with arent really meant to help plants grow. Plants need lots of light. You can buy special lights for plant purposed, but when I tried looking around for bulbs for my hood, i couldnt find good enough ones to put enough watts in the tank. So i ended up buying a new lighting system. With those kinds of bulbs (that you have now), im not even sure if you would have 1 watt per gallon even, and with plants you need AT LEAST 2 watts per gallon. My tank is at 4 watts per gallon, and the plants are doing wonderfully. Let me find you some more info on that and ill post it up for ya

Heres how many watts you need for plants:

Low light plants are generally .5-1.5 watts per gallon (though getting anything to grow at less than 1 is tricky)

Moderate is generally around 2-3 watts per gallon

High light is generally 3+ watts per gallon.

I cant remember the equation to figure out how many watts per gallon you would have... gosh, i know someone else on here knows, so im sure they can help you figure that out, but i know that my tank was one of the kits from walmart, and those lights they have wont do anything for the plants. My suggestion is to look around and find some better bulbs. Good luck

Watts per Gallon (WPG) equation:

Total Watts/Gallons = WPG

Add up the wattage of all your bulbs....For example I have a dual strip light with 2, 20 watt bulbs. So my "Total Watts" is 40.

I have a 29 gallon tank. So my "Gallons" is 29.

So...40/29 = 1.3 WPG

I grow a bunch of different plants with my goldfish:

Amazon Sword
Water Wisteria (now removed but grows like crazy!)
Anacharis (now removed but was a very fast grower)
Vallisneria grass
Anubias

Yesterday I added an Ozelot Sword and some rotala. Both of those actually fall under higher light requirements than what I have, but I wanna see how they grow for me. This brings me to an interesting and somewhat confusing conclusion. WPG is not the best way to determine if you have enough light over your plants. A measure of the lumens in the tank is the ideal way to determine this. However, this is not easily measured so WPG will suffice.

to the OP...do you use a fertilizer for your plants? It seems your swords may be experiencing trace element deficiencies. Try Flourish by Seachem, available at PetsMart (if you have one nearby) or online. (I use www.bigalsonline.com)

Also the brown algae is diatoms. Very typical of a tank with high silicates. And yes more light will help get rid of those or eventually the brown algae will use all of the silicates up and it will start to disappear. Otocinclus catfish are also an option but beware your goldfish may see them as a tasty snack because they are very small.