When you get bored......

[Froggie]

Originally Posted by shimmy

Gate valves are not designed to be used as a throttling valve they are designed to be a 100% open or 100% closed, if you are looking for a valve that is designed to be throttling us a globe valve.
Now I am new to SW fish tanks but I do have a good idea of affects of flow through valves and I do know that when you use a gate valve you with wash out the seat on the valve then it becomes very difficult or impossible to get isolation.

I'd say you're absolutely correct in your comment regarding gate valves.
I think that one of the reasons that the hobby has taken to using them for this application is that small diameter CPVC globe valves are a specialty item. They're high cost and generally unavailable (IPEX doesn't even list them on their website). The same can be said for butterflys and they've some additional real estate requirements.

In all actuality ball valves have better throttling characteristics than gates... but try fine tuning a stiff plastic quarter turn ball valve.

[shimmy]

Originally Posted by Froggie

I'd say you're absolutely correct in your comment regarding gate valves.
I think that one of the reasons that the hobby has taken to using them for this application is that small diameter CPVC globe valves are a specialty item. They're high cost and generally unavailable (IPEX doesn't even list them on their website). The same can be said for butterflys and they've some additional real estate requirements.

In all actuality ball valves have better throttling characteristics than gates... but try fine tuning a stiff plastic quarter turn ball valve.

Yes glob vales are a special item to be found but not impossible and not cheap. I just personally know that nothing can make your day feel like the worst you ever had when you cant isolate a pump because a decision that was easier at the time.
For cost I would recommend the ball valves and put the extra time in to set them just perfect.
By no means im I saying its wrong or cant be done to use gate valves to throttle, but with that said I feel little remorse for people that take the easier at the time approach to projects that should have a little more energy put into them.

[StirCrazy]

Originally Posted by shimmy

Im not trying to start any arguments over this, just making a comment.
Gate valves are not designed to be used as a throttling valve they are designed to be a 100% open or 100% closed, if you are looking for a valve that is designed to be throttling us a globe valve.

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

[mark]

Originally Posted by StirCrazy

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.

[Vancouver Reefer]

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???



Option2:
Centre overflow:


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

[SmallFry]

Originally Posted by Vancouver Reefer

...... do you ever find yourself getting into something and then you get told off by the good lady because you have been sat at a computer for 7 hours!!!!!

Daily..

Those are some really nice drawings. I tried to do something similar using Google Sketchup for my new tank/stand. Failed miserably. Sad really - I spent 7 years programming supercomputers and I still can't drive Google Sketchup.

[argan]

Originally Posted by Vancouver Reefer

let me know if you can see any improvements i could make.


Sump, Frag Tank and Salt mix reservoir:



Sump is middle return style, Skimmer on right, fuge on left:



Manifold style return:



Let me know what you think!!

VR

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.

[Vancouver Reefer]

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.

[mark]

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

pic

[lastlight]

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