Low-light, low-tech algae issues
Where do I start...
I have 2 low-watt, non-CO2 injected tanks. Both run ~1wpg of T5 lighting, and receive no ferts whatsoever. In both tanks are fast growing stems (wisteria, hygro, bacopa, etc.), that grew like weeds at first. GSA (low PO4) is present and growth has all but stopped. I've recently started dosing Excel, and have noticed significant gains daily, but I have a question regarding ferts.
If I were to stop the excel dosing and stick with only dry ferts on an EI schedule, would there be anything to gain? Without an external carbon source can I overcome my algae issues with just balanced nutrients?
I feel like I know the answer to this, but for some reason I need confirmation. By supplying light and all the necessary ferts, growth would be limited only by carbon availability, or am I missing something?
#1 - 30 gallon (36x12)
42w Coralife T5 fixture, Fluorite and light fishload.
Pair of Bolivian rams, 12 (IIRC) harlequin rasboras, 2 SAEs and 4 Ottos.
#2 - 40 gallon (36x18)
48w Current T5 fixture, filter sand, and a higher fishload.
6 G. Tapajos (2"), 10+ Rummy noses and 10+ Cardinal tetras.
Both tanks have a pH of ~7.7, gH 3/4 and <1 kH.
p.s. Sorry for the long post.