I have had my new light (see sig) for about 4 weeks. I went up from a 42w 10000k.( 0.93 to 2.33wpg) I have had an increase in what I think is GSA. I had it before but ever so slightly. now the areas are about size of small eggs. It is quick to return after scraping off. Is this from my tank adjusting to the new light? I did start Sechem dosing a week ago. But nothing changed with the GSA. My diatoms are looking better but that could be from running the magnum hot shot yesterday, with DE.

Excel and Flourish (Flourish trace is dilute Flourish) are not enough fertilizer for a 2+ watts per gallon tank. You need to dose nitrates, phosphates and potasium with that much light. When you don't dose phosphates or even dose too little phosphates, you get green spot algae. Some of your plants will be trying to grow at the rate that the higher light dictates, but will quickly run out of basic nutrients, starving all of the plants. (Unless I am mis interpreting some of your specs.)

I thought that since I had diatoms that my tank has to much silicates and phosphates. So I was not dosing for that for now. I will take a reading on my phosphate level tonight. Do they make a silicate test kit?

For now I am using Seachems
Flourish
Flourish Excel
Iron
Potassium
Nitrogen
Trace

When they are gone I want to switch to dry ferts with Excel.
I see a lot of print on high light needing CO2 or low light (2.0> ) no CO2. I guess my light is medium. Seen nothing on plants and medium light. I still have the 10000k 42w 0.933wpg light. If it would make live easier I would change it back. I don't plan on using C02. Like all hobbyists I have been thinking of making changes in my tank, just not this second. I will try to keep each subject in separate posts. For now I just want to keep the plants green and lush . So far so good. Except for two plants that have diatoms real bad and are sort of limp ( nano anubias, java fern)
I will just work on lights and ferts or do I have do changes all at once? Hope not!

So to end this which light do you suggest I use? (see sig and above)

I was told here that for a low light tank I should only need 1/4 to 1/2 of the standard EI is this true?

After I test when should I use phosphate?

If Trace is diluted Flourish and cheaper can I use the dry ferts with reduced amount of Flourish ?

I know I get confusing when I type. It's the stupid cancer drugs. I am fine just don't think as clear as I did. My family gave me a tank when I first got ill. I love it, 3 yrs later.

Diatom algae is not caused by Silicates or Phosphates in the water column. If this were true we could add these to the water column and they would appear. Nutrients don't cause algae, lack of nutrients causes algae. The algae is induced by ammonia+light. Once this occurs this algae may then feed on silicates and other nutrients which is normal, but this is not how they were induced. If you follow the policy of starving your plants of Phosphates you will not be helping them at all.

If you are adding any form of CO2, whether by gas or by Excel, then the tank qualifies as high tech. The lighting level is then simply a matter of degree and must match the amount of CO2 you are adding. Lower your lighting to your pre-upgrade level and double your dosing for starters. perform multiple water changes as well.

Cheers,

I've had GSA crop up, only when I stop fertilizing for a while. Adding ferts (esp. phosphate) makes it go away. I wouldn't go right back down to less than 1wpg, better to raise your lighting a little if you can to reduce intensity. You will see a time period of adaptation when you change lighting, but remember the more lighting means the plants need more ferts. Increase what you're dosing and start dosing phosphate, forget the test kit. Too much won't hurt anything so why bother testing. If you had algae problems before you increased light, it only stands to reason that increasing light will increase the problem. Fix the problem, and your light might be just fine. What type of lighting/reflectors do you have?

Coralife Freshwater Aqualight- 36" Power Compact Light-1 x 96W

"Corallife CP" 36" 2-21w 10000k
These don't have room for me to add a reflector to. They both have new bulbs so I can use either.

I was sure wrong about Diatoms. I got my nano powerhead and I will instal it today. That will help with circulation of the Excel and other nutrients. I will have to buy Phosphate.

If there's any way you can raise your fixture a few inches - that would probably help out a lot. If not, getting lots of algae eating fish may help but it's hard to say if it will be enough to keep the tank out of trouble. Lots of water changes, ferts, etc. will be needed, at any rate, with lighting that high.

I bought 3 oto's today. I will try to move the light up but it sounds like I will just have to go back to the old light.

Well, if it were me I would try upping ferts for a while and see if it evens out. If you're using Excel, it's not really a low tech tank anymore, with correct ferts and Excel, you should get away with it.

I will let it ride for now I do see the plants looking better. The water test really good. It's golden from the Brown algae. The oto's have not been in there 24hrs yet. I see plant growth and not just on the fast weeds YEAH! Can't wait to play with dry ferts.
I do have some algae now on the intake so we will see. Not sure how long I watch it grow before I would change the wattage. Don't want more problems.
The question I have now is if I change out the bulb to a lower wattage or use the 42w 10k? What is an average wattage for a 24'' Tall 45g?
I like the that everyone wants to rent the new light meter that is talked about on the board. I now totally understand why.....
Is there a classification difference in High tec with CO2 and High tec and excel?