My CO2-less plain-substrate 24g tank plan: will it work?

[strawtarget]

It's a 24-gallon "nanocube" tank, primarily designed for reef aquariums. I'm going to use it for a freshwater community tank, though. The stock lighting is two 36-watt 50/50 10k/actinic lamps for 72 watts total. I don't like the actinic, so I'm going to try to find plain 7500k-ish lamps to swap in. I figure I can use 36 watt lamps (for 3 watts per gallon) or 24 watt lamps (for 2 watts per gallon), depending on what you guys recommend. I've read that as your wattage goes higher, CO2 becomes mandatory, so maybe 48 total watts would be better for me?

I'm going to use a 1" deep layer of 3M ColorQuartz S-grade sand. This is fine-grained smooth sand that is inert (it's coated in ceramic). I'm not going to put fluorite or laterite under it, and I'm not going to use eco-complete or other such stuff. 3M colorquartz only. I am, however, willing to push fertilizer tabs/sticks into plant roots from time to time.

I figure I want 3 kinds of plants.

A. Floating plants to make shade: hornwort, and water sprite.

B. Low-light plants to put in the shady areas of the bottom: anubias in the deepest shade, and java fern in partial shade.

C. Moderate-light plants to put in unshaded areas of the bottom: maybe a "planted" water sprite? Any suggestions for a tallish plant for this profile?

I'm also going to have a driftwood centerpiece with some java moss attached.

So......

1. Considering my lighting, substrate, and lack of CO2, am I being too optimistic with the amount of plants I want to grow?

2. Are these good plant choices?

3. What would YOU put in the unshaded areas of the bottom? I love the look of moneywort and of corkscrew vallisneria, but I'm doubting I'll have enough light for either of those.

 

[Jchillin]

So......

1. Considering my lighting, substrate, and lack of CO2, am I being too optimistic with the amount of plants I want to grow?

Using the math, you'll be at 3wpg if you were to change over to two 36w bulbs. CO2 supplement may be necessary. Flourish Excel would be a decent substitute if you don't want to go for the cash outlay of replenishing the supply. The plants you listed can handle 1wpg.

2. Are these good plant choices?

Indeed.

3. What would YOU put in the unshaded areas of the bottom? I love the look of moneywort and of corkscrew vallisneria, but I'm doubting I'll have enough light for either of those.

Moneywort and Vals will grow in 1wpg IME. Problem with the Vals would be if you supplemented the Excel mentioned above. Vals and Excel do not go together, Excel tends to kill them off.

 

[SparKy697]

I think you will be able to grow just about any thing you want with that amount of light and ferts. The problem I see is the lack of a carbon source. I have 55w cf on a 29 planted and was feeding excel for a while before going to co2 and most everything was slowly dying.

Consider keeping things below 2 WPG if you don't plan on using co2.

 

[ingg]

You have enough light for either of those.

3wpg is a good amount of light, you may find yourself needing CO2 as has been mentioned.

I'd try some of the neater ludwigias like cuba, some reineickii (sp) for color, or I have a new plant called pogostemon yatabeanus that I love in the backdrop.

 

[neilanh]

To start out, only use 1 of the 36W bulbs. that gives you enough light to grow a lot of things to start out without CO2. Then over time you can experiment with more light.

JMO

 

[strawtarget]

I've done some more research on my lighting options, and found that my best option is to just use one 36W bulb as neilanh suggests. That makes for 1.5 watts per gallon.

At this lower light level, will I still need a carbon source like Flourish Excel? Or will I be okay just dosing plain Flourish?

Also, will this lower light level be okay for Moneywort if I pick a nice "sunny" spot for it?

ingg: that pogostemon yatabeanus looks awesome... I'm definitely gonna try picking some up and putting it in the background.

 

[Purrbox]

While a carbon source would be beneficial, you should be able to get away without it.