Whitish gunk from returns after water changes

[danielankeny]

Hi Friends! I need to update my build thread but the tank seems to be doing well.
However, i have a question regarding water changes, and temporary “gunk” coming from returns when I turn the return pump back on.

it’s 76g fiji cube with 20g sump. I’ve been changing 8-10g once weekly. My method is:

1. turn off ATO, gyres and return pump
2. Drain water from display
3. Pump fresh saltwater back into display
4. Turn pumps back on
5. Replace filter floss in sump

the issue is that a quick blast of whitish gunk out of the returns when I turn the return pump back on. It’s cleared within a few minutes, but it still seems sub-ideal.

Should i alter my method? I am only running my return pump (sicce sdc6.0) at 19%, so maybe this implies I should increase the sump flow to minimize gunk accumulation.

any feedback or suggestions would be greatly appreciated, as always.

livestock is 4 soft coral frags, 2 small hitchhiker corals, probably 20 snails, 10 hermits, hitchhiker brittlenstars, 2 peppermin shrimp. 2 hitchhiker clams

i feed 1/4 cube of mysis/blood worm mix 1 time daily. Lights have been on a 50% max intensity acclimation schedule for 10 or 11 weeks.

thank you!

 

[Stephen Glover]

Sounds to me like it’s just detritus of some sort that dislodges from the return line when you start the pump back up. This shouldn’t be an issue and could actually be a treat for your corals.

 

[danielankeny]

Thank you!

 

[uninformed]

More than likely, this is just the bacterial film growing on the piping surfaces. When you have a large, immediate change in velocity, you will tend to slough off loosely adhered material due to the turbulence. This is natural and I wouldn’t give it any worry.

 

[danielankeny]

Thank you!