Alternating MP40s

Ober_Reef · Jan 6, 2022

Hey Everyone,

I have MP40s running on opposite sides of my tank and since I have increase their flow to 60% my substrate is being blown to both opposite sides of the tank creating a low point in the middle and two “mountains” on each side. I’m thinking it’s because they are both running at the same speed in the exact same function. Just wondering everyone’s thoughts and if there was a way to have the two alternate on the same function to see if it would stop whats happening to my substrate.

Attached is a picture that should illustrate what’s happening.

Thanks for any insight !

Fish Think Pink · Jan 6, 2022

PapaPat said:
Hey Everyone,

I have MP40s running on opposite sides of my tank and since I have increase their flow to 60% my substrate is being blown to both opposite sides of the tank creating a low point in the middle and two “mountains” on each side. I’m thinking it’s because they are both running at the same speed in the exact same function. Just wondering everyone’s thoughts and if there was a way to have the two alternate on the same function to see if it would stop whats happening to my substrate.

Attached is a picture that should illustrate what’s happening.

Thanks for any insight !

Have you tried reducing your MP40s flow from maybe 60% to 40%? Can't tell your tank size as no real point of reference other than the wet side MP40, but feel like its a lot smaller tank than mine.

I run MP40s in slave alternate mode, but they are at 45% in my 180 gallon. They aren't my only pumps, as I also have 2 IceCap 4ks at very low coming front to back across top as well as 170 Penguin Marineland submersible power heads (because I had them handy when I setup tank) so they aren't adjustable but they move water along the back since I've got dual overflows in both rear corners.

My advice, play with your settings. Fine sand also move easier because it weighs less, so keep that in mind.

My sand gets like that these days, but due to a crazy diamond goby determined to bury everything in my tank. I flattened my sand and crushed coral out two hours ago, but there are crazy dips and mounds already in tank substrate front this evening.

'start where you are, use what you have, do what you can' - Arthur Ashe, tennis player

Ober_Reef · Jan 6, 2022

Fish Think Pink said:
Have you tried reducing your MP40s flow from maybe 60% to 40%? Can't tell your tank size as no real point of reference other than the wet side MP40, but feel like its a lot smaller tank than mine.

I run MP40s in slave alternate mode, but they are at 45% in my 180 gallon. They aren't my only pumps, as I also have 2 IceCap 4ks at very low coming front to back across top as well as 170 Penguin Marineland submersible power heads (because I had them handy when I setup tank) so they aren't adjustable but they move water along the back since I've got dual overflows in both rear corners.

My advice, play with your settings. Fine sand also move easier because it weighs less, so keep that in mind.

My sand gets like that these days, but due to a crazy diamond goby determined to bury everything in my tank. I flattened my sand and crushed coral out two hours ago, but there are crazy dips and mounds already in tank substrate front this evening.

'start where you are, use what you have, do what you can' - Arthur Ashe, tennis player

Thanks for your response, I have a yellow face goby that adds the the mess! My tank is 90 gallons and I bought the “special grade” sand to try and reduce the trouble of this as much as possible but it does not seem to help. What is slave alternate mode ?