Flow rates. What exactly is moderate flow?

Hi all;

Dumb noob question. I'm trying to quantify what qualifies as moderate flow vs. high flow. Obviously I understand that there are differing levels of flow throughout any given tank, but generally what would you classify as moderate flow? Is 20 to 30x an hour moderate flow? Is high flow up around 50x an hour?

I'm planning to eventually build an LPS dominant tank, but hope to have a few of the easier to keep SPS up near the top where there will be better light and flow.

Is this even something you can quantify out of context of the specific species or tank size?

Thanks for the help!

 

I'd say the guidelines you've already got in mind are on par.

However, it's not uncommon for people with SPS exclusive tanks to have far more than 50x, even up to 100x.

 

like evolved said its 50x to 100x turn over rate for your size of tank. With that said i have mostly softies and have about 70x turn over rate and only a few SPS but you can tell the diff in how they grow. SPS normally grow in a tighter formation the higher rate of flow.

 

Interesting. That is a bit higher than I expected, Leighton, but that is good to know. I wanted to make sure I don't unintentially put a rip-current through my tank that will shred my potential inhabitants .

 

What he didn't mention is that he's using a single MP40 to calculate his turn over rate (and his return pump, which many people do not consider in the flow rate of the tank). However, the type of powerheads (and setting) can be misleading in that regard.

A single MP40 on a variable setting will provide a very broad, non-constant flow. This is quite different than what a powerhead such as an Evo will provide.

Point being: guidelines are just that, don't get too caught up in them.

And for the record, I was not saying you need 50+. I was agreeing with the guideline you had already stated, which is:

low <20x
moderate 30-40x
high >50x

 

Understood. Thanks Evolved!