I'm still having some issues with one of my tanks.

here is some info some tank

- 46 gallon Approx 24" x 24" 22"T

- filtration 1 ehiem 2217 and one ehiem 2213

- light 5 55W CF bulbs @ 6400K. (2.3WPG) The fixture is a coralife deluxe unit. The bulbs were replaced two weeks ago

- C02, 20lb tank, aquamedic regulator, clippard needle valve, aquamedic500 diffuser. 2-3bps I think I'm getting 20-30ppm (drop checker is always bright green) using 4KH solution lab prepared. Solution is replaced once a week.

- fish, 1 juvie german ram. 4 endlers

- temperature is set @ 79

- Water, 35GH, 17KH, 7.8PH

- Plants
Ludwigia Repens (doing very well)
Brown Crypt (seems to be stunted and has never really grown)
Dwarf Sag (slowly dying off)
Dwarf Hair Grass (slowly dying off)
Limnophila sessiflora (melting)
Rotala Rotundifolia (doing very well)
Stargrass (killed it in two weeks)
HC (killed it in two weeks)
Ricca/cyrstalwort) added two weeks ago. (no change)
The tank is lightly planted

Dosing
KNO3 - 1/4 TSP 3X week
PO4 1/16 TSP 3X week
flourish 3X week
(I dose the flourish on a different day then all of the others)

Substrate is 50% fluorite and %50 regular aquarium gravel

So here's what's happening. I set this tank up two months back. At the time I was only was excel only no Co2 no ferts. I noticed that my plants were not really growing and other died within the first two weeks. I decided to add a co2 system to the tank. That was done about a month back. At the same time I removed some fish in order to decrease my bio load, and I stopped dosing excel. Once to CO2 was installed I started dosing as per the list above, and I added a powerhead to increase the circulation. Within day's there was algae growing like crazy and some of the plants began to start dying off. I have a few types of algae. One is green dust algae it only sticks to the glass, another is some type of black algae that is only found on the dwaf sag, and hair algae it's everywhere.

Is this a common occurrence in planted tanks when CO2 is added to a non co2 system?

I could wipe out the tank and start over but I really don't want to do that. I want to understand why this is happening. I am not known to quit and give up. The more I fail at something the more it drives me to learn and improve. I take this invasion of algae and poor plant growth as failure on my part and I take it personal.

I've been trying to solve this problem without posting to many questions in hopes of trying to figure this out myself. At first I thought the problem was that the light was to high so I reduced it. Then I thought the flow was to low so I added a powerhead.

now still I think it's a balancing issue. Perhaps I changed things around to quickly and the plants have yet to adjust. But what do I know I have dead/dying plants and a ton of algae.

Now I'm at the point where I don't know what to try next? Should I just say to hell with it and pack the tank with plants in hopes that the new plants adjust and out compete the algae? Or should I change nothing and try to keep the tank as clean as possible and hope that the plants recover and start growing.

Suggestions please?

Thanks,

Filipe

I assume there is a typo in your specs - don't you just have 2 55 watt bulbs?

It looks to me like you are underdosing fertilizers, assuming you are following the EI dosing method. You seem to be dosing half of the recommended amounts. The Ludwigia is a very competitive plant so I suspect it is getting most of the nutrients and starving the other plants.

L. sessilifolia should grow very vigorously with your conditions, based on my experience, and the fact that it is profoundly noxious weed. I'm not at all sure why it wouldn't compete well with the Ludwigia.

sorry yes it's 2 x 55W bulbs.

I was dosing that amount because from whatI understand dosing at full EI is only for high light densly planted tanks.

Am I wrong ? should I dose full EI ? I was dosing full strength for the first few weeks. It made little difference. So I scaled back.

Can you post a photo of the tank? Also, is your carbonate hardness 17 dKH or 17 ppm? If it is 17 dKH, that is really hard water.

Here are some pictures.

http://i299.photobucket.com/albums/m...1/algae001.jpg

http://i299.photobucket.com/albums/m...1/algae002.jpg

http://i299.photobucket.com/albums/m...1/algae003.jpg

http://i299.photobucket.com/albums/m...1/algae004.jpg


Yes the dKH is 17. We have really hard water here.

I am pretty sure that your measurements of KH and GH are in ppm, not d(degrees), dont think water gets that hard under normal conditions.
You have really low biomass in your tank, add plants - its very important to have a high biomass, if you dont, algae will grow. Make sure your co2 is around 30-40 not 20-30 - your fish will be fine and its not like you have many of them. also, dose more, its really hard to overdose - you can easily go 3 times the norm, it wont increase algae - algae dont need much either way - in other words, you can not done anything at all, and you will have more algae. The only thing to watch out for is phosphates, but even then, you can easily have 4-5ppm without adverse effects. recommended amount is 1-2 though.
Most imporatntly, get more plants in there. you also have a tall tank, so there is definately not too much light. too little if anything.

If it is 17dKH, check that there is nothing in the tank that drives it up - test tap water. 17dKH is really really hard water, consider diluting with %50 RO water. Many plants don’t respond well to hard water - they don’t absorb nutrients as well, however, you can still make it work, just choose plants that are known to do well in harder water

Those readings are correct. We have some of the hardest water in the country.

If that's the case then I would rather try to find plants that will do well in hard water instead of trying to fight it.

You could make the tank an African Cichlid tank. People with those try to get the hardness way up, and they do find plants that will grow well in them. The trouble with adding RO water to reduce the KH is that every time you do a water change you have to try to match that KH, and that soon becomes a job that you probably won't enjoy.

What types of plants would do well with water this hard?

Any suggestions? I'm getting tried of watching plants die.