waterflow question
 

when you calculate the water flow in the tank are you taking the volume from the tank and sump or just the tank.

read what you just said:mrgreen: . the water flow in the tank, so yes you just use the tank.

Steve

sorry maybe i did not ask the question right, If i have a 150 gal tank 100 gal sump and i want to cycle the water 40 times the volume an hour, should it be 40 times the 150 or 250 combined, Just wondering on how big of a pump to get.:mrgreen:

It's usually calculated on the tank volume so in your case base it on the 150g.

you would be looking at a pump or pumps that will give you between 7000 and 8000 gph which would give you your 6000 gph after head loss (based on average setups..)

Steve

IMO that is a lot of flow going through your sump. A lot of people will use a closed loop or in tank powerheads such as Tunze or Seio or Maxijets to give more in tank flow. With that much flow it is also hard to control microbubbles coming back to your display.
For example on my 190g tank I have a closed loop being run by a sequence hammerhead pump (5800gph), 2 Tunze stream 6200 (5300gph X 2) and my return is a quiet one 5000 (1400gph). It gives me roughly 95 times turnover without accounting for any head loss in the pumps which won't be that much as everything is under my tank.

Actualy Ruth it isn't that bad at all, I have 4000gph going through a 33 gal sump, which gives a 121 times turn over just for the sump. if you look at his it would only be a 60X turn over in the sump with 6000gph. If you design it right there won't be bubbles or anything making it through.

Steve

Key words being if you design it right! I know on my 230g when I have tried to up the flow it is bubble city in my display (I didn't design this system). I have always heard for pods, micro and skimmer you want a somewhat slower flow through your fuge/sump. Am I all confused again?

your assuming that there is a fuge in the sump, personaly I don't think a sump is a place for a fuge as it is for equipment. a fuge should be a seperate tank that is filled by a pump and overflows back to the tank this way Pods are given the best chance for survival and you don't have to worry about how to fit it all togeather and optimal flows.

Steve

My refugium is in the sump :redface: but with some baffels in the sump to slow down the flow and reduce bubbles i hope i will be okay. i am thinking on running a mag 18 i have a seio 1500 and a ehiem 2620 closed loop cannister filter i hope this is going to be enough but i can always add another power head. what do you think???
i just did the calculations and it is roughly 4300gph

I think that a lot of us have fuges as part of the sump as getting one that is properly set up as Steve says that overflows into your display can be challenging as far as getting it set up and not look either funny or butt ugly. My experience with canister filters has not been great - they tend to get clogged up and require a lot of maintenance and also seem to really lose their flow so don't know how much I would count on that as a closed loop but if you can keep it free from sludge build up you might be fine. Baffles are not going to slow you flow down but may work well to make the air bubbles pop before getting to your return pump.

I had trouble putting 50x flow through a sump with 3 baffles, couldn't get rid of micro bubble problems. So I guess the key is in the design.