globes valves for this aplication are expensive as heck and not worth it. what we normaly get is ball valves which are horable for throttling, hence most of us use gate valves. In this aplication the gate valve works fine. If we were using a bronze gate then you are 100% corect as they tighten in there track as they close and having them 1/2 open they will chatter and destroy themselves, but the design of the normal gate valve we use is not this way and there for will not present a problem in this case and works very well for throttling.

As for ball valves they are horable and the worst valve you can use in this aplication for throttling as they have a non linear opening quality. I ended up pulling all the balls out of my system and throwing them in the garbage.


One thing I would add is I am against any valves on the return lines unless they are only for isolating for maintenance. throttling a return is just asking for trouble at some point. if you want to varry the flow between the sump and the fuge use line size to do it. if you want to varry flow through the system then throttle the pressure side of the pump.

Steve

See no problem valving the return on a Herbie (only) if the emergency drain is sufficently sized.

a herbie is different, it is the overflow not the return lines and requires adjustment to work, but it is only 1 out of the 3 lines that make up a good herbie that has a valve. what I am talking about is throttling the lines at the sump level, as in the drawing it looks like he will have a valve to restrict the flow into the fuge, and another at the sump. instead restrict the flow to the fuge by reducing the line size. so if you have a 1.5" return then after the dump into the sump reduce down to a 3/4" line if you want a lower flow to the fuge. another way is to make a spray bar in the fuge so your 1.5" line comes to a "T" say a 1.5 in 1" dual outs or 3/4 if you can find one, then get 4 to 6 more "t"s of the new line size so 1" or 3/4" pass through with a 1/2" tap and arange them across the one wall. this will give you a tone of flow through the fuge but it will be difused and even so it will be gental.

Steve

Looks like you will recirculate too much water going through your frag tank and fuge?
I would have the Drains go into the manifold and the return have a dedicated pipe to itself.
then maybe a powerhead or two in the frag and fuge if flow is a problem.

The main reason i wanted the returns to feed the fuge and frag tank is the detritus. I imagine that if i have the drains going into there, the muck will accumulate rather than being taken out by the skimmer and floss in the skimmer chamber????

I do like the idea of throttling down using smaller pipe sizes and spray bars.

I'm feeding my fuge from one of my drains. What little detritus accumulates is easily siphoned out.

pic

Having a smaller tank where you know it's going to accumulate is a plus I think.

Not having the dwg's to scale is a bit of a problem, those dimensions are critical to doing this properly.

Ok so a change of plan. Im going away from the SQWD idea and will be using an OM of some sort. Either build my own or buy one. So i have 2 designs to pick from for tank layout:

Option1:
Rear overflow box, im concerned about the depth of the box not being enough and getting a gurgling sound from my herbie???
http://farm3.static.flickr.com/2543/...ceff66ae_o.jpg


Option2:
Centre overflow:
http://farm3.static.flickr.com/2549/...8081cdff_o.jpg

Which one would you pick based on cost to manufacture, ease of maintenance and also asthetics ( My main concern!, I hate seeing equipment etc, even outside of the tank ).


Mr OM, the drawings are just for ideas and proposed layout, when i build im down to millimeters!! 5 Year engineering apprenticeship fundamentals drilled into me!!!! I cant be bothered to do a fully accurate CAD drawing for something i will be building. If it was for someone else to build, now thats a different story!!!

Any help would be much appreciated

VR

...................and you know i couldnt resist!!!!!

http://farm3.static.flickr.com/2760/...5e7cf710_o.jpg

http://farm3.static.flickr.com/2720/...7eb3706b_o.jpg

:biggrin: