Order of HOB filter media

[snowlynx]

Does it matter what should go on bottom or top?

Top to bottom I have in AC70:

1.Carbon
2.Phosguard/Purigen
3.Matrix
4.Matrix
5.Poly fill

Reason I ask, few times I clean it out all
at once, I get nitrate spike for few days

It would be easier to put poly fil on top
and just replace that sooner

Unless the waste settles mostly on the bottom
then it would clog up the matrix more often

No room for sump at all

I also replaced impeller with the 30 model
so less turn rate, flow was pounding corals

 

[GimpyFin]

The foam pad generally goes on the bottom, like you have, to help catch crud incoming from the bottom, but otherwise it doesn't really matter. You don't even need matrix if you have a decent amount of rock/sand in the tank.

 

[snowlynx]

The foam pad generally goes on the bottom, like you have, to help catch crud incoming from the bottom, but otherwise it doesn't really matter. You don't even need matrix if you have a decent amount of rock/sand in the tank.

Agree with you on ditching Matrix, it does provide extra filtration
hopefully.

Right now I have a 17 gallon and plan to setup 30 gallon long.

Just getting holes drilled is crazy expensive, then cost of
sump, etc..ugh

Why I'm sticking to HOB filter, no budget

 

[GimpyFin]

Cool. Nothing inherently wrong with using hob filters. They can work just fine, especially on smaller tanks.