Found rust on the glass

[dld65]

I woke up this morning and found my royal gramma dead and he was acting fine and eating normally yesterday. Of course I tested everything right away this morning and I had no changes in my water parameters. However later this afternoon I noticed I had rust spots (real rust, not an algae) on my glass. I had one of those magnetic glass cleaners that I just put back in the tank the other day and I had it hanging in this spot. I never would have thought it would have rusted on my glass but apparently it did and I'm thinking that is what killed the fish? I have 3 chromis in the tank that I pulled from it as soon as I found the rust and I'm having a heck of a time scraping it off. Razor blade finally got most of it off but there is still some on there I just can't get off the glass. Any advice and how bad is my tank now? The rust spots were about 1 -2 inches wide and 3 inches high. Exactly the outline of the darn glass cleaner. It is a FOWLR, about 5 months old. I've been trying to find some other posts on rust and haven't seen any yet.
Thanks all for any advice you can give me. Oh, I also noticed tonight that I now have some white thread like algae starting on the glass that was not there about 3 hours ago. Would that come from this as well?

[Kurt_Nelson]

Can't really help with your problem, except to say that I don't think rust is really that bad. If it's just rust, then it's iron based and many folks supplement their tanks with iron. Most phosphate removers are iron based. Now if there was copper leaching out of the magnet, that's a different story. I seem to remember other posts on here from people that had a magnet case crack and didn't realize it until it was oozing rusty colored water. (Another good reason not to store the magnetic cleaners IN the tank!)

I'd be tempted to say that the royal gramma may have died from something totally unrelated to the rust. I'm thinking if the rust was that hard to get off, then it just didn't show up overnight and maybe the additional scrutiny you've given the tank since the death has brought it to your attention. Sometimes we just don't see things unless we're given a reason to look for them.

I have a feeling there are other folks here that have had the "bad magnet" issue and can chime in with first hand help.

[ccCapt]

Rust will not hurt the tank at all. GFO, granular ferric oxide is....basically rust.

I never saw white algae.

[lance]

Are you sure its not coralline algea which is flat and hard and comes in colors like purple and pink and brown.

Then whats used for water flow in there and the tanks size?

[roka64]

I had a marine scraper rust in my tank. That's the reason I tell folks not to leave them in there. I didn't have any fatalities either.
What are your specific water parameters and what other critters do you have in the tank?

[dld65]

Thanks for the responses, my other inhabitants are bank in the tank and seem fine. I only have 3 green chromis in there since the gramma is gone. The tank is only 40 gallons so I had planned on only adding 2 clownfish after I got back from vacation and then I would have been filled to capacity I figured. I have no idea what killed the gramma then. I did have a snail die during the night and I think he may have feasted on him. Maybe he got something from that snail that did him in? My parameters have been steady much to my chagrin. I posted a couple of weeks ago for advice on how to get my nitrates down, they have been steady at 20ppm. I started the process of switching out my crushed coral for PFS the afternoon after the gramma died. I took 1/4 of the coral out and when I tested my nitrates the following morning, they were down to 10. I was so excited. However, I tested them again yesterday, one day later and they were back up to 20 again. Hopefully once I get all the coral out of there it will solve that problem. My ammonia and nitrites are 0 and have been since i cycled 3 -4 months ago. My phospates are holding at .05. Hoping they will go down once the coral is out as well. My calcium can't seem to get above 400 (using Red Sea coral pro salt and RO water), My SG is 1.024 and my temp is 83. My ph is stuck at 7.8 and I'd like to get that up but I don't want to start adding chemicals if I can help it. I just take a long time to acclimate new fish and that gramma was with me for 3 1/2 weeks before she died. I'm thinking my KH is a bit high? It has been at 196. 9. I do twice weekly water changes of 15% each time and have been for the last 4 weeks to try to get these nitrates down. It doesn't work. And I have tested my WC water and that tests at 0 for nitrates and phosphates. I have a HOB Remora and I have 2 powerheads and a canister filter that I also run for water movement. Nothing in the canister at this time although I had run a little bit of carbon in there previously. Anything that stands out that could have caused the gramma's early demise? I don't have much on my live rock at this point, I had to really cut back on my lighting to fight some algae a couple of weeks ago but I'm bringing that back up to 7 or 8 hours a day at this point. I do wonder at times about this live rock - some areas look bleached out and have no growth on them at all. It is mostly the same type of rock mostly Fiji I think. Some is starting to get some color but a couple of chunks are looking bleached and have had a couple of little pieces break off. Almost looks dried out?? And these are pieces on the bottom, not up near the lights. Is that normal??
Thanks again all!