TXIce

Looking for feedback as to whether or not the setup I have would have too much light. I have a 200 gallon tank (7' long x 2' deep x 2' tall). I have constructed a custom hood for the tank and inside that hood I placed 4 2 bulb fixtures. Nothing fancy here...these were just your basic $30 shop light strips from home depot. The fixtures use T8 bulbs and I had purchased 6 32W 6000k "daylight" bulbs and 2 32W 3600k "soft white" bulbs. Going by the old "watts per gallon" rule of thumb (which I know isn't really a very meaningful way to measure the light) I would come up with just barely over 1 watt per gallon: 8 bulbs x 32w = 256 total watts / 200 gallons = 1.28 watts per gallon.

I'd assume, going solely by the watts per gallon estimate, that this would put me into a "low light" category. The lights, when all 8 are on, "looks" really bright to the eye. The plants seem to grow really well (have some water wysteria in there that seems to be growing like a weed plus some java fern and a couple of anubias nana). Something else I have is a TON of algea. I just can't keep it under control. Weekly water changes and a light cycle of only 8 hours, and within a day or two of a water change the water is right back to looking a murky green.

I know there are a lot of factors that come into play and there is no real single answer as to what my problem is...but as a general rule, do I possibly have too much light?

Touch of Sky

Just a few questions ... is the tank heavily planted, do you fertilize, and if so, with what and how much, do you have CO2 or use Excel?

TXIce

I don't know how exactly to quantify "heavily planted". I wouldn't say it is personally. There are only 2 java fern, 2 rather small anubias nana (sp?) and the rest is the water wisteria. It's not super thick and is only planted on either end of the aquarium. Possibly somewhere in the neighborhood of about 15 or so individual stems on either side give or take a few.

As to the fertalizer I had put some of the Flourish root tabs into the substrate and I had been using the Flourish liquid fertalizer dosing as per the instructions on the bottle once a week. I did also have co2. I have a 30# pressurized bottle which was being fed into a ceramic disc diffuser that was placed underneath one of my canister filter intake tubes. I was using a fluval co2 indicator kit and kept the indicator liquid consistently showing green indicating a "proper" amount of co2 (at least per the kits documentation anyways).

I have also been doing a regular 30 to 40% water change every week.

freshyleif

What is the circulation in the tank like? And Just my opinion but that tank need some more plants and I would not add any fertz until after doing so. As far as I know the watts per gallon rule really goes out the window with tanks the size of yours. But I would ask for some other people who have large tanks to see what they are running.

TXIce

I have four canister filters running on the tank right now. All Fluvals: 2 305s with "standard" intake/output tubes and 2 405s with surface skimmer intakes and "standard" output tube. Combined advertised flowrate of 1200 gph so in a perfect world the tank should be getting turned over six times an hour...though I know I'm probably not getting exactly the advertised flowrate all the time.

koldsoup

If you're getting a lot of algae, you probably have too much light. You could add CO2 but you should probably add more plants to make it worthwhile.

inkslinger

I've read some where that "Watts Pr Gallon" dose not go for tanks over 100g
You can read some info :
http://www.plantedtank.net/forums/li...t5-t12-pc.html
http://www.thekrib.com/Lights/

csmith

What's per gallon doesn't work for much of anything. You basically have two T8 bulbs running the length of the tank. I'd say you have low(er) levels of light. I would, however, take the previous advice and fill the tank with more plants. Have a picture of this monster tank?

TXIce

For what it's worth, things are going much better and I think I can say that the answer to the question in my original posts topic is "Yes!". Since my original post I essentially cut the lights in half. Where I originally had the 8 bulbs, I removed 4 of them. Since doing so the tank began to clear up within a couple of days and after a right around two weeks it looks 1000% better. I can actually look down the tank length wise and see out the other side now.

I do. One thing we've never invested in is a good digital camera, so this was a pic I just snapped with my cell phone a few moments ago and I know it's not the best quality...sorry.

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csmith

I like that stand. To answer a question that was asked earlier, that is a very lightly planted tank. That'll cause you issues as well.