aquarium safe plants that are rusting

[Palehorse]

so i bought some silk plants ,a few years back, from a major aquarium retailer (not sure if I'm allowed to say where). they are marked as aquarium safe but pretty much they look like any silk plant from any craft store only they have been mounted into a piece of slate. My concern with them is that they are rusting and I am wondering if it can harm my tanks. The plant has metal strands inside to give it structure, some of which are not adequately covered with plastic and the base seems to be screwed in. the rust is definitely rust and not algae because they have been thoroughly scrubbed and it is only showing on the exposed metal bits. I have 3 such plants in my 75 gallon , 2 large one small, as well as a large one in my 30 gall community tank. I have had quite a bit of unexplained fish loss in both tanks and i wonder if this could be the reason.
I gooled the rust bit and it seems to be a valid concern, but many of the aquarist websites had links to safe plants, many of which are the same as i bought.
I do not want to buy more of the same type, have no interest in a planted tank, and I hate the plastic alternative.
I asked 2 people at the fish store where i bought them and received two different answers.
I am considering using aquarium sealant to cover the exposed bits but I'm not too sure if that's the thing to do.

thanks a bunch



i'm going to try to show pics. the first plant is exactly the same as my smaller, much less rusty plant, and the other is sthe same as my three large plants

 

[jsoong]

Rust is not harmful to your tank .... although a lot of it will stain glass & other stuff & make your tank look ugly.

Planted tank need Iron & one oldtimer trick is to add an iron nail to the substrate & let it rust ... not sure if that really helps the plants as you actually need iron is fairly specific form for the plants.

at any rate, i would put some silicone over the exposed bit of wire to seal it, just for cosmetic reasons.