Need help setting up 75 gallon flow rates

You'll find people disagreeing over turn over rates per total volume for your tank and sump .
As far as im concerned a higher turn over rate of water back to the sump for filtration is better than a lower one ,
Simply because if you have lots of fish/bio load i'd rather turn the water over more than less.
And if you desire to cut down over all flow it's easier to install a valve in front of the pump ( that cost you money ) to cut down on water turn over .
If you find you need MORE turn over , guess what ?
You can put the pump you just bought for 150/200 clams in storage
and lay out another sum of moneys for a larger pump , simply because the smaller one was'int enough in the first place.

And not to even mention the fact WE ALL desire
clean crystal clear water, hence more flow can move miore water back to the tank for "FILTRATION".

I'm not saying turn your tank into "wave world" here
just you mght consider the "down side" of lower turn over rates.

 

I'm just offering what I know from experience take what I offer for what you feel its worth. Are you drilling this tank for bulkheads for the pump you want to dedicate to the circulation of the tank ? Also who ever told you that a Mag 1800 would run that system has not a idea about how much water a 1 inch pipe can drain .. Is the tank reef ready ? As for manifolding these pumps together can't do it if they share any common connection then its going to mess you up.. You will need the one 9.5 to simple lift water from sump to tank this will push about 500 GPH through the sump and allow the skimmer to di its job the dedicated circulation pump has to be fed direct from the tank then you can manifold them to the 2 4 or 6 bulkheads located around the tank to move water currents . I have a few Gen X pumps now and not a good choice you want a Little giant high Volume low pressure pump to circulate not a high pressure high head pump. like a little giant 4MDQX-SC to circulate the water around in this tank..

 

With to much turnover from DT>Sump you end up getting alot of un-skimmed water which you dont want, IMO a mag 9.5 would be fine on this size tank for the return or you can do a mag18 24 or whatever and use a ball valve to slow it's flow

 

LOL I'd ask first off how many drains to sump are there on the tank and then what size .. The 1 in lines most tanks this size have and then as a rule only a single drain to sump will not handle much more then 500 GPH really and if its set on Fall and a straight shot with now drain silencing devices and let to vent its self and suck air then you may be can get to 650 GPH trough a straight to sump with a 1in. pipe.. Maybe ! Lots of variables control that.

Then I say why over power a pump ? I mean a Peter Built can pull a 900 pound John boat but why ? when a small P/U truck can do it just as well and why waste money on paying for a 1800 or 2400 and only use a 1/4 of what it can do by throttling it back ? to match the systems ability to drain the water through the little pipe . Not to mention the wasted pump money up front then you create back pressure and cavatation of the impeller and then a restricted pump makes a lot more heat and eats a lot more electricity.. And the caveatting eats impeller and chevron seals up. And will cause the impellers to shake the magnet to death and they will score the pumps housing.

If you understand pumps and hydraulic principles then you know what over sizing a pump does. And it is all just a waste 4 x's the tanks volume is what many found out yrs ago with the new Berlin methods less is most times more. The 135 I posted is still running with a Mag 12 or 14 ? since 1998 and it looks better now and its still clear as a bell

 

LoL ,
Tang and i "clearly" have 2 diffrent idea's as to how many times a tank's volume should be turned over.
He suggest less' I suggest on the more side of things.
But i will agree with him on one thing here' i would NOT put manifolds and expect one pump to run sevral lines. ( no more than 2 lines for 1 single pump
and would install valves to equalise the lines should they be of diffrent length.

As for suggestions i "suggested" to walsh he should run at the least 1.5 inch x 2
and 1 inch input x 2 .
With no less than 800gph and no higher than 1200gph ( but i rather and do have of the higher gph rating ).
as far as being gravity fed drains ( will drain 900+ gallons for a 1.5 inch drain )
but don't forget there are 2 drains so the potential for draining is doubled ,
Now with that said there are quite a few variables that are unknown here ,
1, length from main pump to tank
2, how many elbows in drains ( will reduce water flow under gravity )


Karma for you MR. Tang , I will agree to to disagree with you i'm sure you have vast knowledge and i respect your input even if we don't see "eye to eye".


P.S why not have a peter built ? when you can pull the "john boat" OR pull the 30 foot twin engine Scarab ? <<<<<

 

Ha. Karma for both.

A couple things first. Heres what Im working with:
a) 75 gallon all glass with a tempered bottom that Ive had for a number of years now. Not RR so I will drill and install bulkheads in the back glass. No overflow boxes installed. I would like to use the pipes as the drains in this case to maximize usable tank space. Like wildreef said above I was thinking (well, via his suggestion) of 2 1.5" diameter drains located at the top of the waterline. Like he said that will give me the potential for 1900 gph draining capacity. One drain in each back corner of the tank.

b) The sump return will probably go straight up via a flexable hose to one of those variable valve things that automatically switches the direction the water will flow. Dont remember the name right now but its got a funny little acronym. From here it will flow to one of the top corners in the back of the tank, each corner having 2 90 degree bends so each branch loses 1 foot head. Maybe. If my math is right. Dont count on it.

b)I havent the foggiest how I will create the circulation portion of the tank. I was considering a single pump flowing around 3000 gph into 2 vertical pipes. Each vert pipe will split via one of those valves that varies the direction in which the water flows and it has a funny name like SCSY or something. You know what Im talkin about here. Same thing as above. Anyway, two of those for a total of 4 outputs, probably 2 running at any given time due to that SCYOSEDFDFFSDS or whatever contraption. The outlets will be all on the back of the tank, two on the top and two on the bottom. I was thinking of putting short runs of loc line on the outlets so I can direct flow. For providing water, I was thinking a single drain for this coming from the center bottom of the back wall covered with a mesh or something so I dont create a Quisenart because I dont like anemonie smoothies.

C) Im a firm believer in KISS, not the band, but the principle. Im worried this is already getting overly complex but what do I know?

 

I have a 72 bowed with a smiliar setup. We use a Mag 7 for the return in our sump and a Hydor Koralia 4....This is a great combination.....

 

I've always gone with the thought

Don't use your return water from your sump in your calculation of flow. Just use Powerheads or Closed loops. As for how much that really depends on what you want to keep.

Measure what you can manipulate and adjust.

 

On a 75g, I would do a mag7 with a 1" standpipe and 3/4" return, should put you at 9-10 times an hour through your sump... As for flow, I turn over my 75g 30+ times an hour with SEIO's.

 

i have a 75 gallon reef... if you want any info, check out my tank build.... should be under my latest topics