What Size Do You Like for Reef Sump in 4x2x2 tank Stand?
 

We intend to build a reef with fish, live rock, and coral. Before we start building our first stand we wanted to get the sump size right because it may be difficult to install if there is not enough room in the stand.

Which brought us to the question of what is the best sump size for a 4x2x2 tank? Should we determine what filters we want before we decide what size the sump should be? Hopefully we have these questions in the right order.

When you look at the sizing for a sump, you really need to make a few decisions first...

a) What skimmer will you have? In-sump or external?
b) Will you incorporate a fuge in the design?
c) How much will the display hold, so that during a power outage, your sump can handle the backflow until your siphon break kicks in.
d) Will you have an ATO system?

I'm sure there are even more questions, but once you answer these, it will help you figure out size. If the skimmer will be in-sump, how big is it and how much room will that compartment require. For some reason, the return area reflects all the evaporation in a reef setup, so if you make that area too small or don't have an ATO to refill it all the time, then you really risk going dry and burning your return pump out.

Though it may sound complicated, sumps really do help as they add water volume to your overal project and that means you have more room for error in everything you do.

I hope that gives you a starting point.

IMO ideally you get the biggest one that fits and go from there. :biggrin:

ageed. sumps look big initially but by the time you're done adding necessary equipment, it can get crammed pretty quickly, mines already 3/4 packed and the skimmers comin' next week! something to consider..

Thank you for your responses. As big as can be installed under the stand. I am thinking of building in such a way as to push the sump into the tank stand from one end, filling the inside area. I will begin learning about filters and such with this info in mind. Thanks again.

Thats exactly what I had to do because of the way my stand was built (before I had even considered a sump when I first started out with a smaller tank). I ended up cutting out one end and shoving the sump in that way. It was pretty tight but I managed to get it in there. The next stand will be built way smrter :wink:

another vote as big as you can. really, why not?

My skimmer is 21 inches tall and sticks out of my sump almost a foot...something to consider. Equipment first trust me lol

Yep, that's what I do!

So you think equipment should be bought first? Then build the sump to fit as best as possible? This could work.

We value all of your opinions. Would you describe what you are thinking about when you say smarter?

May we ask.. Which do you prefer- in-sump or external?

If by fuge you mean refuge for fish to get away from predators, no, we will probably not have the external room for a refuge.

That is interesting.. how much backflow is normal? and should the sump be run at a level lower than the expected overflow?

I will have to find out what a ATO is.. lol.

ATO - Auto top off.

Thank you I just found out from my Son-in-law, Jason. Do you like to design your sump system first and then build the sump for the system? That would seem a smart thing to do.. Will go down to Blue World and see their's today.

Well my dad built this stand and did a fabulous job on it. However the room in the stand doesn't reflect the exterior dimensions. He put some false backing inside (originally it was designed like a bookcase with shelves, I had it oversized for my 48 gallon tank 48"x12"x12". I didn't really think about how versatile the stand needed to be at the time as I was only a year into the hobby, jumped in with not much research on equipment). The stand was built more like a piece of furniture so instead of just putting veneer on the outside to make it pretty, my dad also put veneer on the inside to hide the framing of the stand (it didn't have doors on it back then) which wasted about 2-3" of working space in some spots on the inside. The stand really couldn't be wasted when I upgraded tanks so I took out the shelves and cut a hole through the midsection to accomodate a rubbermaid sump. Eventually an acrylic sump became available which fit but I was limited to only 11.5inches across because of the stand design (4x4s and really heavy materials, I swear an elephant could stand on it easily, maybe even two elephants!).

Here's a pic which might spell it out better, this is the old acrylic sump:

http://i23.photobucket.com/albums/b3...t/sump2005.jpg


My next stand will have a wider area to work in as finding an 11.5" sump is a real pain in the butt also I'd like to get rid of that brace in the middle but I have no idea how one does that in a wooden stand. I suppose I'll go with a metal stand next time, people seem to have success those ones for "openness" below. I ended up getting a custom tank built for the sump which is 36"x11.5"x16" which is about the maximum I could fit in there, it could have been a bit longer but I wanted to tuck my calcium reactor in the stand as well so I left room for that.


Also:
1)I like internal skimmers, if they overflow, they overflow into your sump, no harm done for your floors. However, I have never had an external skimmer.

2)Not every tank needs a refugium and I think they're more work than they're worth. IMO, they're not for everyone (or me anyways)

3)If the power goes out, a fair amount of water will backsiphon through your return hose. Many people will drill a small hole just above the surface of the water so that the tank won't be drained to the level of the return's entry. This way the siphon is broken and you don't end up overflowing your sump. Always run your sump to a level that can hold the extra water of both the backsiphon and the skimmer in case of a power outage or pump failure. A good way to test this is after getting water in the system, keep the sump level very low and mark it. Drill the hole in the return line just above the level of the tank water. Then shut off your tank and skimmer and watch the sump fill. Then measuring the difference between the two you can find a comfortable level to keep the sump water at.

4). An ATO is an Auto Top-Off system to replace evaporated tank water with fresh water. Many people use a float valve for this. Or you can buy complete systems that work electronically. This way the salinity in your tank is stable and not fluctuating while waiting for you to add topoff water manually (and for larger tanks it can be a gallon or two a day). I have my ATO setup with a rubbermaid reservoir that is hooked up to a float valve in my sump. The reservoir holds about a weeks worth of water so I'm not continually having to make water to replenish it. (you can see in the pic above I used a smaller rubbermaid which wasn't as convenient, I had to fill it every 2 days).

If you are a beginner in this hobby, I personally think an in-sump skimmer is a good option because of the risk of leaks on the external.

By a fuge, I mean refugium where you grow special algaes in order to use up excess nutrients from your main display... It's also a good site for various pods (little shrimp like things) to multiply safely before they make the trip up to the display to be eaten by your fish.

As for backflow, look at it this way. When power goes out, you pipes are full of water, but the pump in the sump is not pumping it back up to the display. Your overflow will continue to drain until the water goes below it's openings and your return pipe will become a siphon until little holes you drill in it stop that siphon from sucking your entire display tank back down into your sump where it has no-where to go.

If you search our sumps on here, I'm sure you will find a variety of ones with build threads. Their size doesn't matter, it's just the principles that you should look for.

I would also consider an external pump - it transfers less heat to the tank. When doing this remember you will need to plan room for your pump AND your plumbing. When I did mine I had planned for a external valve to isolate the pump, but I ran out of room so I had to scrap that plan.

Also some people have been saying that taller is better, but this depends on how tall your stand is - if your sump is too tall and you are using an insump skimmer it could be too hard to remove the skimmer from the sump and stand to clean / maintain it. (or the collection cup in my case.

I would definatly include an ATO, as well as baffells to prevent microbubbles from entering your display.

I had similar experiences here. Built my stand way before I had even considered a sump, in the end I had to remove parts of the stand to fit the biggest sump I posibly could.
Try and buy your equipment before building a sump, that way you can custom fit everything as needed. There is no point having a huge skimmer area if you end up with a skimmer with a small footprint, on the other had, if you end up having a larger skimmer, you'll want to make sure you have enough room to fit it in. When you are selecting a skimmer, be sure you have enough vertical clearance in the stand to be able to easily remove the collection cup for cleaning, this was a really big issue for me as there wasn't alot of vertical space inside my stand.. Alot of skimmers are 20"+ and then need a bit more for the removal of the cup, just something to watch for.
As mentiioned a in an earlier post, make your return section as large as possible if you aren't going to be using an ATO. As the rest of the sumps water levels are maintained by baffles or dividers, any evap will cause the water level in the return section to drop, you don't want the pump cavatating/sucking air as water in the system evaporates. I lose about a gallon / day.
You'll also want to leave space for any heaters/probes/ phosban reactors etc etc, lots to consider .
A good site to start at is:
here
HTH :)

Wow you guys and girls are amazing. What good info.

What you all seem to be saying is buy the internal skimmer, external pump, ATO with baffles, external heater, and determine the return size according to your tank size and return hoses, etc. to set your baffle placements. I know i have missed some things like reactors. thanks for the heads up.

Then design the sump and (sump overhead room for plumbing) and stand to fit. Here's a question: Have you ever considered installing/building in a rubber floor under the sump to catch any spills?

# 1 reccomendation, read as much as posible before you build, it's simple to make changes now, not so simple after you've already started :)

yeah I say there's a 90% chance you'll want to do things differently a couple years from now and get a completely different tank. Don't stress too much. I agree that an auto-top off unit is VERY desirable and an in sump skimmer is just fine.

One important thing is to consider is how to get water into the top off resevoir when it's in the stand. If the stand's not built yet maybe make it tall enough to get a small bucket into the stand to dump water in. Otherwise scooping water in with a little rubbermaid container SUCKS :)

Do you have room surrounding the tanks in case you want to add a refugium, another system, etc etc? If so then you shouldn't have to stress too much right now because you can add as you go.

Thats the only way I've had to rebuild twice,another tip dont go by manufacturers dimensions that was the reason for one of my rebuilds. I just bought a new skimmer and built the sump around it,the water level is perfect for my skimmer and doesnt fluctate because of special baffles, and I went with a lower tank to gain better access to my collection cup its a dream to work with trust me equipment first lol

heres another pointer setup the feed hose for your skimmer run it into a five gallon bucket and time how long it takes to fill,from that you can calculate your pump size. A little underpowered is good,it lets you adjust flow from the skimmer side because if you turn the valve on the pump side down you'll put strain on the pump due to backpressure and prematurelly burn out your pump

Hi Dab, is it a good thing to have a little less flow through the skimmer? And why?

If any flow needs to be turned down it should be the skimmer flow not the flow off the pump side so a pump that pumps a little less than the skimmer is better than a pump that pumps more than the skimmer make sense? When they sell pumps its rated by head (length of vertical pump) now if you also run this through a partially closed valve it increases your head/backpressure to a point your pump cant handle. This is all based on the fact that you will have a flow control valve on both the in and out lines in your sump

So it is preferable to slow down the flow after the skimmer? Have I got that right?

yes,the supply line for your sump just after the overflow/skimmer.


a SLIGHTLLY weaker pump will acomplish this for an example say your overflow flows at 310gph a good pump to use would be a 300. Dont forget to account for head for example I have 4 foot of rise from my sump so my pump needs to pump 300gph at 4 foot of head.......its easier than it sounds lol good luck

If you already have the pump that flows alot more than you need and you're worried about back preasure, just tee a line w/ball valve into the return and run it back to the entry section of your sump. You can then run your pump wide open and send any excess back through the sump

That sounds like a good suggestion. So we divert a portion of the flow off the pump back to the sump entry point from a point just after the pump output. ok.