Rust looking corrosion

[fishman]

All
I battled green carpet algea and slime for about 2 years and finally beat it! I kept scrubbing it each week and finally won. However now Im struggling with red slime. Not to bad, but just keeps forming on my rocks. Also I keep noticing on like my intake screens of my pumps it turn a rust looking color. Im running phosban and have been for some 1-1.5 years. I dont ever turn the phosban reactor all the way up but Im wondering if this might be what this is? My corals and fish are all well. I also notice in my trash can that I mix RODI water in with my salt that the side of the trashcan is rusty looking as well. I have done no pump work and after each water change I rinse the trash can out. Any ideas? I dont run carbon and all I add is CA and AK each night. Tank has been up and running for 4 years. Also I notice on the LR there is what appears to be dirt like looking stuff that flows in the current. When I scrub on it with a toothbrush it comes off easily. Very odd stuff. Bacteria maybe?

 

[dsmlrussell]

Sounds like Diatoms to me.

 

[melosu58]

Almost sounds like diatoms also to me.

 

[MT79]

Also I keep noticing on like my intake screens of my pumps it turn a rust looking color. Im running phosban... Im wondering if this might be what this is?

Does it blow/rinse off easily? If not I would suspect diatoms or some other type of algae. Many times diatoms are a sign of high silicate. The fact you have red slime makes me think you might have elevated PO4 levels present as well. Do you use RO/DI water? If so what is the TDS? Can you list your water parameters -SG, Ph, Ca, Alk, Temp, ammo, nitrite, nitrate, PO4?
High PO4 and/or Silicate levels in your source water may explain the rusty algae growth in the SW mixing can as well.

 

[fishman]

I use RODI and even have a 2nd cannister I run through for PO4. Plus I use a P04 reactor on my tank. I dont know how I could have ANY P04. I dont have a test kit but will get the LFS to do so. I keep my SG at 1.022 or 1.021. PH is around 8.0-8.2 Temp at 79-80. No ammonia trites and less than 5 trates. I just ordered some new phosban to run in my tank. I havent changed it in like 3 months.