What size return pump?

[mdavis735]

I have a friend who is setting up a 90g salt water tank.He will have a 30g sump.Does anyone know what size pump he will need?I think he is gonna go with a mag drive,but what number would be best?

[topsoil]

sort of depends on how much flow he wants going through the sump. I am setting up a 90 right now, with a 800 gph pump. it probably is only pushing 500 or so once you factor in the 4' head. The flow seems to be ok in my sump. not too slow, not too fast.

[mdavis735]

thanks for your reply.i know there is supposed to be a formula as to how many gph you need to get the right turn over based on tank size,but i have know idea what it is.lol.

[topsoil]

I decided I would make up for any lack of flow through the sump with powerheads in the main tank. I figure I need enough flow to keep the skimmer working ok, but not so much that it's noisy in the overflow. I think I'm limited anyway since my overflow is a 1-1/4". I think I read it won't flow much more than 600 for every 1" bulkhead.

[coraline79]

I am running 600 gph return on my 30 gallon, and setting up 1500 ghp(at 4 foot head) return on my 125.

[fishn]

Mag 7 or 9.5 would work

[alton]

I used a mag 18 on my 75g with a 1" bulk head and a 6' lift. Most of your external pumps are accurate when it comes to GPH charts. Mag pumps although great pumps drop GPH very fast as you increase the lift heights. Much safer to go with external pumps for return, if you go with insump pumps use GFCI protection.

[dustint21]

I have a MAG 7 on my 90RR oceanic! It has one 600gph overflow box. I think about 3.5ft of head space! I run my pump and return wide open and have had no problems! The MAG 7 matches the overflow perfect! Oh and I have a 30 gallon sump!

http://i61.photobucket.com/albums/h59/dustint21/017-1.jpg
http://i61.photobucket.com/albums/h59/dustint21/009.jpg
http://i61.photobucket.com/albums/h59/dustint21/025.jpg

Hope this helps! Good luck!

[mdavis735]

wow dustin thats almost the exact setup he has.i noticed your sump is a diy tank with dividers.did you do it or someone else?i think if you would be interested he would love for you to school him on how you set that all up..he doesnt know what to do.i dont either.i was lucky.i got a corner tank that was drilled and only has a overflow with flex pipe and a return.so all i had to do was hook up one clear plastic hose.

[ErikH]

google pressure locking sump baffles, it's a cool idea. :)

Essentially, you just need to have a return that ultimately is slower than your overflow, otherwise it's flood time. I use a mag5 on my 75 and a 7 on my 48. Funny how that worked out, I may switch them today...

[dustint21]

I would be happy to help! Only problem is Im in killeen! I did this all myself! Its not hard! The way mine is setup I dont really need all the baffles but it doesnt hurt! Its really easy after the first one! I am leaving on Thursday for Army training (JRTC) and will be gone for a month! So PM me and I wil give youmy number!

[mdavis735]

thats cool.we actually both live in andice.which is only like 30 miles from killeen.i will pm you.

[fishn]

I tried the presure lock baffles and they are VERY hard to get right. They are either to loose or to tight. On my new sump I just used the aquarium sealent thet they sell at Home Depot and glued them in.