plant problems

basically i just wanted a link to a good site that i can reference to, but i am having problems with my myrio with the leaves turning yellow, then brown then just disintigrating...and now the older leaves on the cobomba are turning yellow, i'm thinking lack of nutrients somewhere, but prolly more likely lack of co2, which i was hoping to avoid injecting and use just flourish excel, but i will prolly have to start doing that.
 
I agree with Rex, you are most definately straving those plants. The cheapest way to remedy that will be with dry ferts, either from a local hydroponics shop or from Greg Watson online. For dosing regiemes check out www.csd.net and Rex's site.
 
AquariaCentral.com