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Dave-H
07-27-2010, 06:19 PM
Hello all -

Well, my tank is cycling away and I'm ready to put some plants inside. My tank is a 55g corner unit and I can fit a 24 inch light housing up top. There is about 21 inches between the glass top of the tank and the substrate (flourite) down below.

I purchased lights from the lfs when I bought the tank and the guy at the store was quite confident in the lights he sold me, but of course I wanted to ask around to be sure.

Right now I have 2 Coralife bulbs, each says F18-T8-BP - 10,000 k. The lights appear to illuminate the tank nicely, although the far corner (in the back) is a bit dimmer than the rest of the tank. That is ok with me.

What I really want to do is have some nice ground cover type plants growing in there. In the [distant] past I have had problems with moss growing completely out of control and taking over the tank, so I'd like to try something else.

My questions are:

1) Is the above light arrange enough to support a planted aquarium of 55 gallons and 20 inch height?

2) Would this be considered low light, medium? high?

3) Any recommendations for a good ground cover type of plant that would do well in these conditions?

I am hoping not to do a co2 setup if possible.

thanks!! Dave

Plant Man
07-27-2010, 06:24 PM
Are the bulbs 21 watts (normal output) or 39watts (high output) each.

Dave-H
07-27-2010, 06:31 PM
Unfortunately I'm not sure - I am out of town so I had my wife read what was printed on the bulb before I posted!

Coralife
F18-T8-BP
10,000 k
120 volt 60 watt

Should the normal/high output be printed on the bulb?? how do I tell>

Plant Man
07-27-2010, 06:42 PM
Unfortunately I'm not sure - I am out of town so I had my wife read what was printed on the bulb before I posted!

Coralife
F18-T8-BP
10,000 k
120 volt 60 watt

Should the normal/high output be printed on the bulb?? how do I tell>

If it's not on the bulb you'll need to look at the box the lamp came in or find it online.

Dave-H
07-27-2010, 07:01 PM
Wife says:

The box says R-12562, and there is a sticker with the number 26430. But. not information about whether it's a normal or high output light.

I am having trouble finding any details about this online!

Brhino
07-27-2010, 07:18 PM
F18 - 18W fluorescent
T8 - tube shaped with 1" diameter (the number represents eighths of an inch)
BP - bi-pin (the end type)

Stole that from some other forums. T8 bulbs only come in one type, they're not like T5 where there's a high output version. Only 18W each means you don't have much light in that tank at all, from the standpoint of growing plants. Also, the 10,000k spectrum is okay but not ideal for growing plants. So, all in all, I think you're going to need something a lot beefier to grow any plants besides those with the lowest lighting requirements.

Dave-H
07-27-2010, 08:14 PM
Ahh ok, that's a starting point.

So, I am a little confused how to choose another bulb. Do I need a new fixture? I know there is a formula for the number of watts per gallon (something like that) but does that take into account the shape/depth of the tank or is it just a rule of thumb?

Also, I am hoping to get lighting to that not just adequate, but actually a great setup that the plants will thrive under. I'm not looking to spend unlimited funds, I just want to get the right lighting setup.

Are there any efficiency concerns with these lights? We've been making our house energy efficient (interesting project) so I'm hoping to make the lighting as energy efficient as they can possibly be without compromising the effectiveness of the lighting.

I have read about lighting on the internet, but I'm having a hard time choosing :(

Brhino
07-27-2010, 08:22 PM
Do I need a new fixture?
Yes, you'll need a new fixture. You cannot just stick a higher wattage bulb in a lower wattage fixture and get more light out.


I know there is a formula for the number of watts per gallon (something like that) but does that take into account the shape/depth of the tank or is it just a rule of thumb?
it's just a rule of thumb. It also doesn't take into account style of bulb, spectrum of the bulb, etc.


Are there any efficiency concerns with these lights?
High-output bulbs are less efficient, yeah.


I have read about lighting on the internet, but I'm having a hard time choosing :(
I know a lot of people around here just buy shop lights from hardware stores and get plant grow bulbs for them. It may be a tricky for you trying to fit a rectangular light fixture on a corner tank. If you can't fit anything larger than a 24" fixture, your options may be limited.

rich311k
07-27-2010, 08:23 PM
To get more wattage you would need a new fixtuure, T-5 high out put fixtures are very efficient.

Dave-H
07-27-2010, 08:27 PM
Unfortunately I can't get anything larger than a 24 inch fixture, unless there is a triangular fixture out there!

I can probably return the fixture/bulbs to the shop, since I was very clear that I wanted something that could light the tank adequately for plants to be very healthy and they assured me that this would fine.

I'm a bit confused about the spectrum if 10k isn't right, do I want a higher spectrum or lower??

Brhino
07-27-2010, 08:28 PM
6500k is generally considered to be the ideal spectrum for plants.

Dave-H
07-27-2010, 09:10 PM
Maybe something like this (http://www.marinedepot.com/ps_ViewItem.aspx?category=AquaticLife_T5_HO_4_Lamp _Light_Fixtures_w_Lunar_LEDs_24_Inch_T5_Fluorescen t_Light_Fixtures&vendor=AquaticLife&idProduct=AK01035&IdCategory=FILTFIT54U&child=AK01035&tab=4&size=24%20Inch%20%284%20x%2024%20watt%29)would do the trick! Lot's of light and I like the idea of the nighttime LED.

One concern is that these types of lights seems to be suspended on 4 legs, presumably to keep the hot lights off from heating up the water and themselves. Doesn't that allow escaped light to shine all over the place? I like the sleek, tidy appearance of my current light housing, albeit underpowered.

Also, is there any problem with using this kind of light on my glass cover? Will the glass reduce the effectiveness of the lights?

Brhino
07-27-2010, 09:34 PM
the lights are recessed inside the fixture, so all light that escapes it is going to be directed in a downward cone. It won't matter that it's stood off from the tank a bit. There will be a little bit of light lost due to the glass, but not a significant amount.

One thing to make sure before ordering a light fixture like that is if it's a freshwater plant fixture or a saltwater coral fixture. Most companies sell both versions on any given fixture. The spectrum on a saltwater fixture will be different, and it'll be more conductive to growing algae than plants in a freshwater tank.

Dave-H
07-27-2010, 11:11 PM
There's another model (http://www.marinedepot.com/AquaticLife_T5_HO_Light_Fixture_W_Lunar_LEDs_Fresh water_T5_Fluorescent_Light_Fixtures_for_Aquariums-AquaticLife-AK010352-FWLTFIT5-vi.html) just like the one above that is specific to freshwater, with a 6000k daytime light and the LEDs at night. I like the idea that it has the nighttime lights and that they run on timers, etc.

Very cool, and it has tons of good reviews online.

My only concern is the appearance. I understand that the light has to be on legs above the surface of the tank rather than flush with the glass top like my current light fixture. But, it seems like it will be leaking out light all over the place, and I see some comments about this in the reviews.

I am hoping that I'll be able to place some material around the top of the light so that it forms a sort of flange around the light. That would reduce the amount of light leaking out of the top while still allowing ventilation. Anyone tried something like that?

Dave-H
07-28-2010, 07:42 PM
I ordered that last model that I posted above - should be here in a few days! Very exciting, and now I can start planning a custom light visor. I love a complicated DIY project (as evidenced by my floor leveling and python plumbing work!).

I did have this question, though: the Aqueon 54 can fit a 24 inch light, but just barely. The shape of the tank leaves quite a small space for the light. Am I correct in understanding that I should just set the light up on it's 4 legs right on top of the glass? Will the glass reduce the effectiveness of the light? Cause heat to build up? Or is this just fine?

Brhino
07-28-2010, 07:50 PM
that should be fine.

You should post some pictures of your setup. In the way-off future when I have money for such things, I've got an eye on the larger version of the aqueon corner tank. I'd love to see how yours looks.

Dave-H
07-28-2010, 07:51 PM
Ok, I'd be happy to once I get back to Denver (I'm in NYC on business).

Plant Man
07-29-2010, 02:10 PM
Ok, I'd be happy to once I get back to Denver (I'm in NYC on business).

Good choices Dave! Just remember if your not running Co2 keep T-5 under 1.2 watts or so or you may end up with lots of BBA.

Dave-H
07-29-2010, 02:23 PM
Good choices Dave! Just remember if your not running Co2 keep T-5 under 1.2 watts or so or you may end up with lots of BBA.

Uhh... what's BBA? :)

Plant Man
07-29-2010, 02:30 PM
Uhh... what's BBA? :)

Black Beard Algae.

If you get it, don't worry you can wipe it out with Excel at triple the dose for about a week. but you'll still need to solve why you got it in the first place or you'll get it again.


This is what it looks like before and after after Excel has killed it. It turns red and then falls off afetr about 2 weeks.

http://i131.photobucket.com/albums/p296/TheMailman6666/co2025.jpg
http://i131.photobucket.com/albums/p296/TheMailman6666/-2515.jpg

Here's the same plant about 3 weeks later,

http://i131.photobucket.com/albums/p296/TheMailman6666/timelaps16-4010.jpg

It's not nessesary to remove your plants to rid them of BBA.

Dave-H
07-29-2010, 02:34 PM
Good choices Dave! Just remember if your not running Co2 keep T-5 under 1.2 watts or so or you may end up with lots of BBA.

Also, per my calculation the lights will are:

* (2) 24" T5 HO 39W 6,000K Lamps
* (2) 24" T5 HO 39W Roseate Lamps
* (2) 1W Lunar LED`s

and (disregarding the LED's) will generate 156W of total light, divided by 54 gallons = 2.88 watts per gallon. However, this deep corner tank doesn't allow for great light distribution and is 22 inches deep so I 'm not sure that level of light would reach the far back or side corners.

Still, is this too much light and will get algae growing? Would it be OK to consider putting some kind of snails, shrimp, etc. to manage the algae? This is planned to be a planted tank with small community fish (i.e. guppies and neons only) so maybe an algae eater would fit in.

Any advice appreciated! For the time being, I'm hoping to avoid having to deal with a CO2 setup.

Dave-H
07-29-2010, 02:38 PM
Ahhh... isn't there anything that could live in the tank and feast on that algae? Also, can anyone confirm that my watts/gallon calculation above is correct? I understand that that is just a rule of thumb, but I'm trying to understand lighting as much as possible.

Piscine
07-29-2010, 03:53 PM
Snails will eat algae, at least mine do anyway. Mine also nibble on my plants sometimes.

I personally do not think you need so much light. Also, keep in mind that overly bright lights can bother fish.

Dave-H
07-29-2010, 03:58 PM
Hmm.. I never thought of having too much light.
No matter how hard I try, I can't seem to find the 'perfect' light for my tank!

Plant Man
07-29-2010, 04:04 PM
Also, per my calculation the lights will are:

* (2) 24" T5 HO 39W 6,000K Lamps
* (2) 24" T5 HO 39W Roseate Lamps
* (2) 1W Lunar LED`s

and (disregarding the LED's) will generate 156W of total light, divided by 54 gallons = 2.88 watts per gallon. However, this deep corner tank doesn't allow for great light distribution and is 22 inches deep so I 'm not sure that level of light would reach the far back or side corners.

Still, is this too much light and will get algae growing? Would it be OK to consider putting some kind of snails, shrimp, etc. to manage the algae? This is planned to be a planted tank with small community fish (i.e. guppies and neons only) so maybe an algae eater would fit in.

Any advice appreciated! For the time being, I'm hoping to avoid having to deal with a CO2 setup.

WAY, WAY to much light. T-5 is very efficient light. Half that light would be about right. 1.4 watts of T-5 is good light to grow anything with Co2.

This is .91 watts of T-5,

http://i131.photobucket.com/albums/p296/TheMailman6666/5thweekEI.jpg

Dave-H
07-29-2010, 04:46 PM
I'm hoping not to use CO2. Would 1.4 watts/gallon still be a good amount of light?

Dave-H
07-29-2010, 05:25 PM
I wonder if this (http://www.marinedepot.com/AquaticLife_T5_HO_Light_Link_Fixture_FreshWater_24 _Inch_T5_Fluorescent_Light_Fixtures-AquaticLife-AK01142-FILTFIT54U-vi.html)would be a better choice, then. That takes me down to about 48w on a 55 gallon tank.

I guess the problem is that it's easy to understand that I'm looking for a 6000k lamp in a 24 inch housing, but as for the actual brightness it's hard to say. The watts/gallon is just a rule of thumb, I know, but if the T5 are so much brighter than it makes that rule hard to use even as a guide.

Is there another metric, i.e. lumens, etc?

Plant Man
07-29-2010, 11:03 PM
I wonder if this (http://www.marinedepot.com/AquaticLife_T5_HO_Light_Link_Fixture_FreshWater_24 _Inch_T5_Fluorescent_Light_Fixtures-AquaticLife-AK01142-FILTFIT54U-vi.html)would be a better choice, then. That takes me down to about 48w on a 55 gallon tank.

I guess the problem is that it's easy to understand that I'm looking for a 6000k lamp in a 24 inch housing, but as for the actual brightness it's hard to say. The watts/gallon is just a rule of thumb, I know, but if the T5 are so much brighter than it makes that rule hard to use even as a guide.

Is there another metric, i.e. lumens, etc?

T-5 are great, see if you can find a T-5 lamp that puts you in the 1 to just over 1.4 watt per gallon. I think that may work for you.

You really chould consider Co2 if you can. It makes everything so much easier. Especially with low light.

Dave-H
07-30-2010, 06:06 PM
I really like the fact that my current fixture sits right on the glass, though. I am still wondering if I could put some other type of bulb in there - I just don't understand the technical part of that. There are replacement bulbs available, lots of them, so I wonder if just a bit more power would get me there.

Dave-H
08-01-2010, 03:56 PM
After discussing this with a trusted friend, I went to the lfs and bought a Coralife Freshwater Aqualight T-5 strip. This might be a winner because it sits right on the glass and barely heats up at all, produces nice looking light, and is actually a much lower profile than my existing housing so the cosmetic is good.

The 30 inch puts out 18 watts of 6700x and 18 watts of Colormax Full-Spectrum light. According to the lfs, this should give me a decent low lighting solution and it was very inexpensive. Only problem is that it doesn't light up the back of the tank well because the 30 inch unit only fits towards the front of the tank (due to the corner shape). However, there is quite a bit of room towards the back to add another 24 inch unit and the two combined should be more then enough to do some basic low-light plants that can be healthy without CO2.

They also had a very cool 12 inch LED that would give some ripple and make the back of the tank look awesome, I'm sure. However, it sits up a couple of inches off the glass so we are back at the same issue, trying to meet the cosmetic needs (simple top with no huge lights leaking out).

Having TWO of these T-5 strips by adding the 24 inch version would add another 14 + 14 watts of light towards the back of the tank, for a total of 64 watts of T-5. According to the lfs, that is moving me closer to the 'moderate/mid' lighting range or on the upper range of the 'low light' and the plants should do great without any CO2.

Does this sound like a good solution? I've already got the 30 inch on the tank and it looks great both in the water and on top of the tank!

Plant Man
08-02-2010, 04:09 AM
After discussing this with a trusted friend, I went to the lfs and bought a Coralife Freshwater Aqualight T-5 strip. This might be a winner because it sits right on the glass and barely heats up at all, produces nice looking light, and is actually a much lower profile than my existing housing so the cosmetic is good.

The 30 inch puts out 18 watts of 6700x and 18 watts of Colormax Full-Spectrum light. According to the lfs, this should give me a decent low lighting solution and it was very inexpensive. Only problem is that it doesn't light up the back of the tank well because the 30 inch unit only fits towards the front of the tank (due to the corner shape). However, there is quite a bit of room towards the back to add another 24 inch unit and the two combined should be more then enough to do some basic low-light plants that can be healthy without CO2.

They also had a very cool 12 inch LED that would give some ripple and make the back of the tank look awesome, I'm sure. However, it sits up a couple of inches off the glass so we are back at the same issue, trying to meet the cosmetic needs (simple top with no huge lights leaking out).

Having TWO of these T-5 strips by adding the 24 inch version would add another 14 + 14 watts of light towards the back of the tank, for a total of 64 watts of T-5. According to the lfs, that is moving me closer to the 'moderate/mid' lighting range or on the upper range of the 'low light' and the plants should do great without any CO2.

Does this sound like a good solution? I've already got the 30 inch on the tank and it looks great both in the water and on top of the tank!

Yes, 1.16 watts per gallon should be just perfect! Good for you. If you had co2 on with this light your tanks plants would love you. But I think you can certainly keep them alive/growing (slowly) without it.

What are you filtering the tank with?

Do you have a power head to keep circulation up?

These are great,

http://i131.photobucket.com/albums/p296/TheMailman6666/hydor_koralia.jpg

Dave-H
08-02-2010, 03:53 PM
Yes, 1.16 watts per gallon should be just perfect! Good for you. If you had co2 on with this light your tanks plants would love you. But I think you can certainly keep them alive/growing (slowly) without it.

What are you filtering the tank with?

Do you have a power head to keep circulation up?

These are great,

http://i131.photobucket.com/albums/p296/TheMailman6666/hydor_koralia.jpg

No powerhead, no. I have the output from the filter aimed in just way so that I have some fast moving water in one corner, nice gentle current elsewhere, and the filter intake towards the very back of the corner tank, behind a bit pile of driftwood. I'm not sure but I'm hoping that this will be enough water movement - there is enough agitation on the surface to send tiny bubbles moving around and the water seems healthy enough.

But, I'm not sure if I actually need more water movement. It seems ok to me.

I ran into a problem with the lights, though. If I put the 24 inch strip on the tank I won't be able to move it very far towards the rear of the tank because of the corner shape. Really it will only be an inch or two behind the 30 inch strip light and that puts it right over the center of the tank rather than towards the back. Maybe this is ok, but I am hoping to light the rear of the tank.

There is also a plastic piece at the rear of the cover, so the whole back 10 inches of the tank isn't covered by glass. Tricky lighting situation!

Plant Man
08-02-2010, 06:29 PM
No powerhead, no. I have the output from the filter aimed in just way so that I have some fast moving water in one corner, nice gentle current elsewhere, and the filter intake towards the very back of the corner tank, behind a bit pile of driftwood. I'm not sure but I'm hoping that this will be enough water movement - there is enough agitation on the surface to send tiny bubbles moving around and the water seems healthy enough.

But, I'm not sure if I actually need more water movement. It seems ok to me.

I ran into a problem with the lights, though. If I put the 24 inch strip on the tank I won't be able to move it very far towards the rear of the tank because of the corner shape. Really it will only be an inch or two behind the 30 inch strip light and that puts it right over the center of the tank rather than towards the back. Maybe this is ok, but I am hoping to light the rear of the tank.

There is also a plastic piece at the rear of the cover, so the whole back 10 inches of the tank isn't covered by glass. Tricky lighting situation!

In a low Co2 situation you want as much water movement as you can get. My suggestion it you get a powerhead to improve movement.

As far as lighting, yes, you have a very tricky situation there. I wonder if you can find an even shorted t-5 then 24" for the back. Maybe have a High Output on the front and a smaller Normal Output on the back.

Or what about something like this for the back corner?
http://www.bigalsonline.com/BigAlsUS/ctl3684/cp18369/si4185907/cl0/macrogloadjustablerefugiumlight15w
http://i131.photobucket.com/albums/p296/TheMailman6666/img8311343med.jpg

I have also considered a corner tank as my next project. i am very interested in how you solve this situation.

Good luck.

Dave-H
08-02-2010, 09:39 PM
Ok, I'm going to look closely at how much water movement I have and consider adding a powerhead. I am using an Eheim 2336 and the output has quite a current - after much fooling around I figured out an angle that will provide fast moving water around much of the tank, and nice slow current in some other areas. This looks pretty good to me but maybe I can do a bit better. I like a 'mellow' sort of tank so I don't want too much movement in there but if it's better for the plants I will check it out.

The lamp that you suggested may work, but I have this unusual requirement in that the tank is in our living room and part of my agreement with my wife is that it be reasonably simple/attractive to look at. That means no hanging/pendant lights or bright lights leaking out the sides, etc.

The Coralive T5 double strip is just perfect because it can sit right on the glass - low profile and no light leaking out (well, nominal) so I'm liking that one. If there was a 12 inch unit that I could stick in the back that would be a big winner.

The one that you suggested might send light all over the corner of our living room since it looks like it can't sit right on the glass. I wonder, however, if something like this (http://www.bigalsonline.com/BigAlsUS/ctl3684/cp18366/si2989513/cl0/currentusa1225powerbriteledlightfixture10000kdayli ght)would be ok. What's great about that unit is that it runs cool and is SHORT so I could put it perpendicular to the other light, with one end in a far corner/rear of the tank - that would really give a nice light distribution and will sit right on the glass.

What makes this hard for me is that it's tough to compare the light - I wonder how much power this light puts out in terms of how much it will benefit the plants, etc.

Regardless, I think that putting a perpendicular light from the rear corner might be a good way to go if I can find one that will sit right on the glass top. Getting a glass/acryilic corner piece to replace the black plastic that came with the hood/cover seems easy enough.

Dave-H
08-03-2010, 06:29 AM
This (http://www.directaquarium.com/Coralife-Mini-Freshwater-Aqualight-Compact-2X9W-9-p/11015.htm)could work although it's not that strong and has been discontinued. I wonder if I could find one.

Plant Man
08-03-2010, 02:12 PM
12.25" Powerbrite LED Light Fixture (10,000K Daylight)

I think this is much better then what I suggested, good find! It says it's a 10,000K so you really can't go to wrong with that. I would definitely give that one a try, if it lights up the back your set.

Dave-H
08-03-2010, 03:24 PM
12.25" Powerbrite LED Light Fixture (10,000K Daylight)

I think this is much better then what I suggested, good find! It says it's a 10,000K so you really can't go to wrong with that. I would definitely give that one a try, if it lights up the back your set.

Awesome! This can really work well because it will sit right on the glass for cosmetic purposes and I like the way that LED's work. Another benefit of this approach is that if the light is not strong enough, I can simply add another strip because these are linkable.

I wanted to ask: how do I estimate the power of this strip so that I decide whether I need 1 or 2?

My other 'best' option is to take a 12 inch fluorescent housing and retrofit it with a 2 x 9 watt CF setup. That's about the same price, but I'd have to do a bit of work to get it going. I wonder if two LED's would be more effective light than 18 watts of CF.

If I get two, I can have an LED against the back wall (well, say 6 inches out from it) on either side of the tank - a triangular light setup for a triangular tank! Very slick!

Plant Man
08-03-2010, 04:27 PM
I wanted to ask: how do I estimate the power of this strip so that I decide whether I need 1 or 2?

The only way I can think of (without a light meter) would be to compare it visually to the T-5.

There is not a lot of info on growing plants under LEDs yet so you'd been doing us all a favor by letting us all know who it works out. I would stick with a least one T-5 unit at the front and use the LED or two LED units for the back/middle. You want to light the tank as evenly as possible.


I'd do it like this,

http://i131.photobucket.com/albums/p296/TheMailman6666/tanklights.jpg


Or this,

http://i131.photobucket.com/albums/p296/TheMailman6666/tanklights2.jpg

Dave-H
08-12-2010, 06:07 PM
Well, I'm at the airport waiting for a flight back home, and my wife tells me there's a package for me - it's the Powerbrite LED strips! I ordered two of them for starters. I can't wait to set them up and see how it looks!

If I get home before the tank lights go off, I'll set them up tonight and snap a photo so you can see how it looks. I'm curious to see how this affects the plants. I could add 1 or 2 more of them if need be, and they are super efficient with little heat output so if they can keep the plants happy this will be a winner.

Dave-H
08-13-2010, 09:02 PM
Yes, 1.16 watts per gallon should be just perfect! Good for you. If you had co2 on with this light your tanks plants would love you. But I think you can certainly keep them alive/growing (slowly) without it.

What are you filtering the tank with?

Do you have a power head to keep circulation up?

These are great,

http://i131.photobucket.com/albums/p296/TheMailman6666/hydor_koralia.jpg

Well, I did some analysis of the water circulation of the tank. My technique was to stare at the tank for a long time :)

I found that there is actually great circulation in the tank, with gentle but steady current in most areas and some rushing water towards the top of the tank near the output of the filter.

However, there are two slightly 'dead' spots in the tank:

One is the rightmost corner of the tank (it's a corner unit) in the first couple of inches of water. If I put a floating cube of dried tubifex woms in that area, it will eventually sit on the side of the tank and not move around. This dead spot is really small, though - maybe 2-3 inches in the extreme corner.

The other spot is in the exteme rear of the tank. It's not exactly still water, but the water moves so slowly there that a piece of floating food will just float around in slow circles in that area. We are talking about the rearmost 4 or 5 inches of the tank, the far back corner. I can't tell but it appears that this slow/still water extends far towards the bottom of the tank. At the very bottom of the tank, near the rear corner is the intake for the Eheim 2336 filter with the pre-filter attachment, which sits on the bottom. So, there must be some decent flow there just from the intake.

I'm having a hard time knowing if I should add a powerhead to keep things moving - the plants on one side of the tank are swaying about as much as seems reasonable without hurting them. The plants on the other side are barely moving- almost imperceptibly but they do move around a bit.

I was thinking that if I used a small powerhead like the one you mentioned above (is it this (http://www.aquariumguys.com/hydor-koralia-pump.html)?) it might be too much flow! I am going for a planted tank with a light population of neon tetras, guppies, shrimp, snails, frogs.

So, I'm not sure if I need more circulation or if an additional powerhead will turn the tank into a wild ride for these little fish, all of whom look quite happy!