My dilemma is between 2 tanks, the problem is I don't know which one is causing the smell.

Tank 1) I recently put together a 40 breeder bombina tank, 3/4 water and using peat brick as a natural barrier and water is 6-7". Between the cork background I am using and the peat bricks the water is still red after being cycled for 2 months but I don't know which is causing the red. This tank is planted and has a waterfall/stream feature as well as fish in the water.

Tank 1) I recently brought in a 20L for 2 Leopard Geckos that I rescued to bring back to life. They are shedding on a regular basis, soaking on their own and the females eyes are now both in the process of returning. Healthy and fat now, I wouldn't think they would smell. Also I clean their tank out about 2xs a week. Use the sand substrate, vines, slate, and bark in there.

Now that the Leos are healthy again I am willing to adopt them out, but I thoroughly dislike the 40B now with the red water.

Any suggestions on where the smell(s) might be coming from or how to get rid of the red water?