Help!! Melting crypts and algae
Hi, first I’d like to thank everyone who takes the time to read this, I know it’s a lot of information. I’m new to aquariums and am trying to figure out what I have done wrong. I have what were sold to me as low maintenance plants that wouldn’t need fertilizer, CO2, or high lighting (I was told the light that I had would be sufficient, it came with the lid to the tank). An anubias nana petite attached to drift wood, a tall crypt (spiralis), a little bush like crypt (Undulata), a marimo moss ball, and several stalks of water wee(elodea or anacharis).
The nana petite on the driftwood was added to the tank on March 10th, the moss ball was added on March 17th, the two crypts were added March 18th, and the water weed was added March 24th. All of the plants were in tanks at the store when I bought them.
I started to notice some browning and yellowing in the leaves of the Undulata along with some holes in the nana petite shortly after getting them all planted. I went out and bought some easy green liquid fertilizer and root tabs and put three tabs in, near to each plant with roots in the substrate, and did a dose of liquid. That was a little over two weeks ago , so there’s been three liquid doses. I see tons of growth in the weed, that guy actually looks pretty good, and some new grown in the tall crypt. Nothing new seems to be happening with the nana, but I’m not sure that’s surprising since apparently it’s a very slow grower, but it does have some black hair algae growing on it now. The Undulata is “melting” constantly, it’s leaves are turning yellow and then becoming see through and disintegrating. I can also see green film like algae on the glass of the tank and brown looking stuff on the mermaid decoration. I put some water in a white cup to see if it was green but it looked more like a light yellow/brown.
I don’t have CO2 set up, I’m not even really sure what all that is or involves. It seems complicated when I try and search it and I’m not sure I want to fool all that. I was told the fish would provide CO2 for the type of plants I have. I get lots of bubbles from the flow on my two filters, again, I was told this would be sufficient to oxygenate the water. I leave the light on for like 10 hours.
I have 0 ammonia, 0 nitrite, and between 40-80 nitrate. I do water changes once or twice a week, depending on my Nitrate levels.
I think that’s all the information you would need, but I’m new at all this so please ask if you need any more. Sorry this is so long, I tried watching some YouTube videos and asking questions there and never received any answers.
Questions: Why is the Undulata melting so much? Do I need CO2 now that I’m adding ferts? Should I stop adding ferts? What should I do about the BB and green film algae? Have I done anything glaringly wrong???