aquaman555

Needing a little help with T-5HO lighting for a 20 gallon X high, which is 23.8" tall and needs a 20" fixture. I currently have a 29g with 65w PC(which is a little much) w/ DIY CO2, that I will switch the plants and fish to the new tank. I am seeing few 20" fixtures, some being 2 x 18w and some 2 x 20w.

I plan on going pressurized CO2 soon after it is setup, will be dosing with Seachem Flourish + their NPK ferts.

I am kind of unfamiliar with T5HOs and their equivalent output compared to power compacts. So I am looking for any suggestions on fixtures and also should I only run 1 bulb while still using DIY Co2? Any tips on fertilizing, I would prefer dosing only once or twice a week if possible.

Current plants are Amazon sword, dwarf hairgrass, wisteria, ludwigia repens, crypt wendetii and plan on adding some different plants after the switch.

Thanks in advance for any input. I've been into planted tanks for about a year and have learned a lot and battled a lot of algae as well. I was a reef guy and the thing I learned after researching was I was thinking too high of lighting and my biggest mistake was not realizing planted tanks weren't as light needy as reef tanks and that it takes more than dosing the simple one bottle of fertilizer like it's portrayed at big chains.

aquaman555

Anyone? I am concerned whether 40 watts of T5HO will be enough for such a tall tank, especially once I go pressurized. Any input would be appreciated. I am making a move soon and want to have the 20g setup at the new place before taking down the 29.

Seattle_Aquarist

Hi aquaman555,

Actually a PC would be a good choice for a 23"+ tank. An AH Supply 1X36 watt PC kit (17.5" long) with an MIRO 4 reflector should give you about 50 PAR at the substrate level.

Here is my 24" tall tank with an AHS PC kit installed.

aquaman555

Roy, thank you very much for your reply.

I had actually been pondering the idea of a 36w PC. Now with the addition of pressurized CO2, would I want to add more lighting? I guess this would be more dependent on plant types whether it would actually be necessary, correct?

Also great looking tank, what type of substrate is that? Amazonia maybe?

Thanks

Seattle_Aquarist

Hi aquaman555,

You are absolutely correct, when I was planning my tank first I decided on if I was going to want to grow low, medium, or high light plants then I chose my light / reflector.

Thanks for the complement, the substrate is Soilmaster Select Charcoal which unfortunately has been discontinued by the manufacturer. I have heard that aquariumplants.com substrate (in Black Diamond color) is very similar. I am looking at using Safe-T Sorb 7941 which is also a heat treated Montmorillonite Clay product but has more varied particle sizes and colors.

aquaman555

Thanks again, I really like the greyish color of your substrate.

Correct me if I'm wrong, but I'm assuming 36 watts of T5HO would be stronger in comparison to 36 watts of power compact?

Seattle_Aquarist

Hi aquaman55,

I don't know if we can make that statement; here is a link that might provide a more complete answer but the simple answer is "maybe". A 2X18 watt T5HO and a 1X36 watt PC put out about the same amount of light (assuming the ballasts are not undersized). If the 2X18 watt T5HO has an individual high quality reflector for each bulb it will provide higher PAR levels than a PC, even a high quality PC like AHS. On the other hand if there is only one reflector for the multiple bulb array then the PC with a quality reflector may provide more usable light.

aquaman555

Thanks for the explanation and link. Helps me out a lot.

Seattle_Aquarist

Glad to help aquaman555!

digital_gods

Aquaman,
I good alternative till you get your dream fixture would be couple clip on reflectors and 26w spiral daylight bulbs from your local home improvement store or walwart. DFWAPC has had good sucess and par readings with this fixture setup. The hemispherical shape of the reflector helps to focus the direction of the light.