New tank setup questions (sump and waterflow)

Im not sure if the plastic tub would be the best idea for a sump. You may be better off using a 20 gallon long and then just adding the baffles by siliconing in Plexiglas. The only real drawback to that is you will need to drill the tank (about $20)

I think the tupperware may be too flimsy to really incorporate a stable dripplate..

When you talk of drilling the tank, were you talking about the 20 gallon sump?

Yes, as opposed to using a tupperware/walmart plastic container

Is this for the dirty drain to the skimmer and the clean drain to the tank? (2 holes, both near the bottom) and what size?

yes probably on opposite ends of the tank 1.25" diam

The CPR and the SOS are very similar. Neither uses round tubes, but a flattened siphon. If I build an over flow box, what dimension would each side Tank side / back side box need to be and would a 1" or 1 1/4" bulkhead be better? Would 1/4" plexi be adequate?

As far as the size it depends You need to have it large enough to handle the flow I would think 3" from to back 5-6" top to bottom 5-6 " wide definitely do not use anything smaller than 1.5" 1" is not going to work

Also, what about the protein skimmer, good enough?, and could I just set it in my dirty side and pump water through it over to the drip plate? It runs off a power head.

It should fit in to the main pumps capacity dirty from the tank side -- to skimmer
Drain from skimmer into the clean side of the sump mag 5 then returns it back to the tank
So if the skimmer dosnt supply enough water too the mag 5 the mag will drain that side
You could always control the return to the tank with a valve, but that defeats the purpose of the pump
Your skimmer should equal the flow of the main pump

Would a mag drive 5 be good enough to pump the clean water back to the tank.

Sounds good

Also, on the spray bar return, is the tee in the middle better, or could you just come off one end (ell shape)and run across the back?

No, definitely use a T in the middle. You'd be surprised how much of a difference being slightly off balance does to controlling the flow underwater. Use a T with as equal right and left pieces with as equal holes as you can figure out. If you get then close the flow inside your tank will be beautifully equal

Still a few more questions or areas for clarification. I have decided to use the 20 gal aquarium (no Rubbermaid) for the sump and to drill my 75 gallon tank (no overflow box).

That's a good idea

You allow room in your sump for overflow water. This being the amount of water from top of overflow tubes to the top of the tank.

The sump should be able to hold

The amount of water in the tank from the utmost filled position, to the lowest point of the bulkhead
Also taking into account that overtime the tank could he heavy or light on evaporation or the amount of water changed
Plus enough of water to "prime" the entire works. The sump its self will need a an inch or 2 above its bulkhead so It dosnt suck in air.

What will happen is the water in the tank will need to be sufficient height to drain (your desired operating level controlled by a valve)

Doesn'tt the height of the overflow tube control the amount of water in your tank?

Basically how much water you have in the sump will dictate how much water is in the tank.

How could you ever get more water in your tank than the top of the overflows?

If you had more water in the sump(than the tank could hold) and the overflow drain clogs- the tank overflows.
If you pump in water faster than you drain it- the tank overflows.
If your overflows are too small- the tank overflows.

Anyway assuming you can, is there some amount of space better than others for the top of the overflow tube to placed from the top of the tank? I was thinking of placing the bulkheads about 4" (do you agree) from the top (I read somewhere that 4" is a close as you should drill to the edge of an aquarium), then using an elbow and a short piece of PVC to turn the overflow up to the height I wanted to keep my water level. This would be about 1" from the top of the tank.

No!

Typically (rule of thumb drilling overflows) *usually* you want to drill the bulkhead so it is as physically high as possible, s that the outer ring of the bulkhead is just below the black plastic ring that's on most aquariums. 4" is way too low!

Divide your tank size (gallons) by height this will give you gallons per inch. then figure how close you are in regards to evaporation working water in the sump without ever over filling the tank OR the sump

Is this (approx. 3.75 gallons) enough. Otherwise the water level will be visible while viewing the tank.

Ideally you want the water level *not* to be visible- it should be just about the black plastic ring. You can control that with a valve on the drain side(overflow) of the tank

If I have this little of overflow water and I am using a 20 gallon sump, would I want to leave just 4-5 gallons of empty space in the sump and use the rest (15 gal) for working water?

Im picturing this in my head and I would think a 20 gallon is about as small as I would go.

About the tank overflow bulkheads, you like 1.5". Is this size really important? I think I read that a 1" flows 600 gph??? I was only wanting to turn my water (75 main +15 sump?) 6X an hour (total 540 gallons and hour). 6x per hour is minimal

Do not waste your time, effort money and tank on trying to use 1" for a drain 1.25 is the smallest 1" for pumping in is good but not for draining. You can get it to work but one wrong kink in the hose or small fluctuation of the outgoing water, and the pipe get an air pocket and the tank overflows, use 1.25 and be sure to include some venting for the drain tubing

I am not trying to cheap out, just the smaller the bulkhead and pipe in my tank, the less noticeable it is. If I use two overflow bulkheads instead of one, would 2 smaller  or 1" be okay? Is the size of pipe running down to the sump the same as the bulkhead fitting?

Yes it should/must be the same size

If your only going to use one bulkhead then it should be plumbed with rigid tubing and not flexible. Also,you need a direct vent, best to do in a relatively vertical straight line

My protein skimmer (venturi) has " fittings in and out. Will this be okay (flow enough)?

Well the skimmer can kind of loop in the sump if it has to It can just overflow the internal baffle. Ideally it should match your main pump, which is what I suggested the smaller model

For my return pump, I was going to use a Magdrive 5. Should I go up to a Magdrive 7 and use a valve to control the return? Is the diameter of the return and the spraybar important? Also if I use quarter inch holes, what number would be right to flow the 5-600 gph

See page 72

When I drill the bulkhead and place the outer ring near the black rim, all of the bulkhead fitting will be below the black rim, right?

Yes- you want the top of the ring of the bulkhead just below the black ring, Im pretty sure 4" is much lower than that

Do I put an elbow on the bulkhead and turn it up to keep my level up above (or near) the black tank rim?

Sure, that helps control the flow in a day to day working, however in the event of a power outage due to the elbow not being glued water will seep until it gets to the lowest point of the bulkhead.

Do the estimations above and send me the figures gallons per inch do the sump as well

Tank 3.75 gallons per inch, Sump 1.5 gallons per inch.note: what I was trying to ask, if I have 3.75 gallon (This assumes I have 1" of space above my fitting to the top of my tank) of tank overflow water space, would I (assuming a 20 gallon sump) want to try and keep 15 gallons of working water in the sump?Or are you saying, I need to not have more water in my sump than my tank can handle above the bulkhead fittings? If so that would be a total of 3.75 gallons of water in the sump?

You need to estimate

How many inches you need to keep the sumps bulkhead underwater (assuming all water is pumped into the tank)
Add the inches/gallons to operate the tank
Allow a few inches for a buffer and you can then judge if the 20 is going to make it

AND...

So all the above calculated water will never overflow the sump

(I realize this overflow reserve will depend on how high I can get my bulkhead fittings mounted and how well they flow vs. the amount of return flow.)What I don't know is which is more likely to need the reserve area for overflow water (during a problem), the sump or the tank.

The sump definitely, once the power goes off all the water ends up in the sump

I would think the sump would and that a 5 gallon reserve area would be fine. Then the only problem would be if (as you suggested) the overflow was to plug and the return pump pumped (overflowed) all the sump water in to the tank. Is this probable?

Its definitely possible. The likeliness of it happening is dependent on

What size pipe you use (I recommend min of 1.25)
If this drain is adequately vented
One hole is more likely to get blocked than 2, so in the event you have a komokazzi fish or anemone thinking the overflow pipe is a good hideout, if there is only one hole.... your sunk.
You can block it with grating but overtime this will become encrusted and algae covered, so again 2 are better than one

Hope you can understand what I am asking. Also, I would like to have 3-4 gallons for evaporation and fluctuations in water changes.

A 75 gal could probably afford at most to be + or - 2 or no more than 3 gallons of evaporation. Please note you will not *see* the waterline go down in the tank... it goes gown in the sump ;-)

As far as water changes just be careful so as not to put in an extra gallon or 2 as this will add up, its also best to do a "simulated" outage after a change so your sure the volume is correct

For my return pump, I was going to use a Magdrive 5. Should I go up to a Magdrive 7 and use a valve to control the return? Do I understand correctly, you would rather be a little under pump wise rather than over pumped and control return volume with a valve?

Based on your skimmer, the stronger pump is over kill and overall would not be balanced. Its a water to restrict a pump on the output side. Again your skimmer pump and main pump should be as closely matched as possible

I had originally planned no valve in the overflow drain and a valve to control flow in the return line.

Well it depends you can install valves where you need them. I would think a valve out the outside of the overflow will give you the control you need. Whetehr a valve is needed to tone the pump down is dependent on the pump. as a general statement, I dont think you need it. However you can always add one if you need to.

I feel as I am getting closer to understanding what I need, please bear with me.

No problem, I think you will get feeling of accomplishment (experience) once this is done and in place, once you see everything flowing and working flawlessly... you'll know why