I have a 12 gal eclipse without co2 added to tank, what plants do you suggest to place in this size tank. I also like to have guppies, corys, so need to be safe and ok for them as well? IF I do the DIY co2, will it hurt my fish? Also, Will plant fertilizer hurt my fish? Thanks.

The lighting is not very strong in that tank so you want to look at low light plants like java fern.

I was actually thinking of Java Fern Lace and I already have Java Moss.

Try anubias petite and other mosses. I am also having success with blyxa in my little 3 gallon with no CO2. I do use Excel though, just a couple drops here and there.

I have the same tank for my shrimp. I put some wisteria in there and its growing really well. Along with a anubis nana makes it look great. Best of luck with it.

java moss would be a good choice too. if your not going to add CO2 or increase the amount of light, use a piece of wood and tie java moss over it. you might also want to put some fern at the rear corners of the tank and a couple of small, broken pieces of wood at the forgound.

DIY-ed CO2 shouldnt hurt the fish as long as you follow the recipe. but be very careful as a small tank like yours will experience changes very quickly. so go easy with the CO2.

plant fertilizer won't hurt your fish. but again be very careful when dosing them since the tank is small. remember to carry out water changes weekly. or every 3-4 days if your tank is heavily stocked. (java moss and fern won't take up the nitrate from fish waste fast enough to inhibit algae growth)

hope that helps. good luck!

Very helpful suggestions. I appreciate it.