Shopping Choices

[India]

I'm setting up my first sump - an Ecosystem-type refugium for caulerpa export for my 90 gal. I'm using a 20 gal glass tank w/ siliconed glass dividers. The flow will be in the neighborhood of 300-500gph (I don't have the pump yet)
I'd like to use a 1" pvc system...I have an Amiracle overflow.

I'm shopping at Savco, and there are too many choices!

I thought I'd get the bulkhead/strainer set, but I really don't know if I want single thread, double thread, etc....would it be better to purchase the parts seperately to get a particular type of bulkhead? and if I do get the set, what is the right angle for? .

Incidentally, do I match the bulkhead hole to the pump height, or use a flexible connection?

How do I decide between flexible and rigid PVC in general? The Overflow already has a length of rigid PVC attached to the bulkhead - shall I extend that with flex to make it easier to position, adjust and service the system parts? A complete rigid assembly seems difficult to form and manoever...
Regarding my return lines: (I would like to use a Y near the pump, and run one return to each corner of the tank) Should the whole assembly be rigid? or is there an advantage to using all or partial flex?

I don't have a drilled tank...what do I use to bring the return lines over the lip, and connect to return nozzles? How would they be anchored?

Do I want a Gate or Ball valve and which model?
Do I need a valve on the supply line? I would think it easiest to simply disable the overflow...
I would think I need a regulating valve between the pump and the Y in my return lines (isn't that how I control flow thru the system?) I don't know how to decise which type of valve is best suited...

Are their check valves really all they're cracked up to be? I sure would like to avoid leaving half my sump empty to allow for back flow...But I need to be sure the valve won't restrict my flow, and that it will be easy to service...

Thank you very much for help...I'm sure these are boring questions for those in the know, but what's a newby to do??!
Much Appreciation,
India

[pm_devin]

First off I would say to buy the grey schedule 80 bulkheads, they are much better than the cheap black ones.

I believe the right angle is just to direct the water downward.

I would wait until you get your pump, then drill your hole you never know you might change your mind about something. Yes you would drill the hole for the bulkhead to the height of the pump input and yes I would use either flexible PVC or flex tubing to reduce vibration.

How do I decide between flexible and rigid PVC in general?
Using flexible tubing will greatly reduce head loss on your returns.

I don't have a drilled tank...what do I use to bring the return lines over the lip, and connect to return nozzles? How would they be anchored? If your going to have your sump drilled why not drill your tank?

Do I want a Gate or Ball valve and which model?
I would just use union ball valves.

Do I need a valve on the supply line? I would think it easiest to simply disable the overflow...
Put a union ball valve on the output side of your return pump, and after the Y if you so desire.

Sorry, I don't know anything about check valves.

Good luck,
Pat

[India]

Thank you very much, Pat...I appreciate the information...I'm going to take my sump in to a glass company to have it drilled...I can't do that with my 94gal tank - it's been running for 2 years...
India

[Teo]

the left side diagram is how I went over the top of mine.
when I did it like the diagram on the right, I couldn't get the lock line turned down soon enough and couldn'd slide my light back far enough, but you may not have this problem and can leave out the 45deg fitting.
The way I have mine does lock to the top of the glass well enough though.
hope this gave you an idea or two, good luck.

[India]

Thank you, Tim, that's just the kind of info I need...it holds tight w/out clamps, etc?

[Zephrant]

In general, if you anticipate trying to get a fine adjustment of the water flow, use a gate valve, all other places a ball valve should be fine, and cheaper.

I don't like check valves, because they tend to restrict the flow, and leak due to accumulated debris (worms, sponges, etc... ). All it takes is a little something on the seal, and it drips water though it. If is not a very reliable device to prevent a sump overflow. There is also a problem with it chattering- if the water is moving fast when it tries to close, it can bounce open, then close, then open... self-feeding until the water stops. i.e. it completely fails to stop the water as advertised.

That said, I'm sure many people use them. But many people use hang on overflows, and I don't like them either. ;)

I suggest using flex every place you can- less vibration from the pump, and less head loss if you are doing sweeping curves instead of tight 90's.

Zeph

[GROSSR]

Being that you are getting it drilled, get it drilled with two holes. One hole about 3/4 of an inch higher than the other. The reason is for blockage.

The first hole is your real drain. In the even that something blocks that hole and you aren't home or don't notice it, the second hole can handle it.

I have a 90 with a 10 gallon refuge. I opted for an overflow. My prevention device is a float switch which will turn on if the water gets to high.

Good luck.

[India]

Grossr, I appreciate your info - please let me make sure I understand it...I should install 2 sump return bulkheads, and join the tubes with a valve before they go into my return pump? And the concern is that, even with baffles and a strainer, one could clog and leave the pump to run dry?

And 2, your insurance against back siphoning during a power outage is a float valve...where is it placed, and what does it control please?
Thank you,
India

[GROSSR]

Sorry, I misread your post. I thought you had a seperate refuge from your sump.

I have a seperate refuge from the sump. My mistake.

If temperature is not an issue, would your pump fit inside the sump? If not, in your has one hole is just fine.

As far a high water, you would only need a float valve for a low water condition.

For high water, turn off the pump and see how much water flows down into the sump, from the overflow and from the return line. Adust your water level in the sump to compensate for the backflow.