Circulation And Diatoms

[sydney19]

I recently started a 20 gal long planted aquarium. I have had many aquariums but this is the first one I have had fully stocked with live plants, so I am new to the planted tank world. It has been up and running (and cycled) for about 8 weeks and no plants seem to be flourishing. 

I have a T5 high output dual lamp with a 6700k bulb and a 10,000k bulb
I am running a fluval 30 hang on the back
And a smaller air pump with an anchored air stone. One that is sufficient for a 20 gal tank (says the label) but does not create much movement in the water.
I have about 1.5 inches of flourite and about .5 inches of pool sand on top of the flourite for a substrate.

the only chemicals i add occasionally are CO2 booster (i do not have a CO2 injector) and flourish.

First question: why am I getting diatoms? and how do I get rid of them?
Second question: Do I have enough circulation, should I add more if I am noticing plant matter sitting stagnant on the leaves of the plants?
Third questions: Am I doing something I shouldn't be? Does anyone see any red flags with what I have running in my tank?

Any and all advice is welcomed!! 

 

[gmc1]

Diatoms are normal on all new tanks.eventually they will go.i personally would create more flow with a small pump.it can take a while for some plants to establish themselves especially in a new tank.eventually you will get a balance where everything will be ok.

 

[Byron]

If by "diatoms" you are referring to the brown algae that will easily wipe off with your fingertip, then as gmc1 said this is common in new tanks.  However, if you mean something else (I have been battling a diatom bloom of slightly cloudy water, brownish organics here and there, in only one of my seven tanks) that could be different.
 
To your plant issue, the first thing I see is the high intensity light.  I will be honest and suggest that you are not going to resolve things unless you can reduce this intensity by at least half (will one tube light without the second?) which may mean a different fixture.  The problem now is that the intense light is driving photosynthesis, but there is no way near sufficient nutrients to allow plants to do this.
 
To the nutrients, CO2 is a major factor here, as there will never be sufficient in an aquarium to balance such high light.  [If you reduced the light intensity you can balance the naturally-occurring CO2.]  But the other essential nutrients are alos going to be insufficient.  A liquid comprehensive fertilizer may supply these adequately.
 
I would myself not mess with diffused CO2 in a small tank like a 20g, depending upon what sort of "planted tank" you want in the end.  The liquid carbon supplements like the API CO2 Booster is not the same thing, and without getting into this issue, I will just say that this chemical (glutaraldehyde) is something I would never put in a tank with fish.
 
Byron.

 

[StevenF]

 
 
the only chemicals i add occasionally are CO2 booster (i do not have a CO2 injector) and flourish.

What type of Flourish.  There are multiple types and some are designed to be used with other flourish fertilizers but not alone.  Using the wrong type of flourish with high lighting would probably cause plant growth to stall due to nutrient depletion.   Since you are new to this I would start with Flourish comprehensive.  but with high lighting and CO2 you may need to use more comprehensive than the label recommends to prevent nutrient depletion.  comprehensive contains all of the nutrients your plants need and is intended to be used by itself.    Also with the air stone operating  you shouldn't need any CO2 until the plants start growing.  once the plants start growing you can restart the CO2 and  then maybe return to full lighting.