really basic questions

markak15 · 08-14-2005, 06:49 PM

I'm toying with the idea of getting a bigger tank. So far I haven't exceeded 20 gallons. I don't really understand the whole overflow/sump/drilling thing. So let's see if I have this right. The best way to do things is get your tank drilled, which means the water can drain directly out of the tank through this hole, and into the sump. Then it's pumped back to the main tank. The overflow box is for if your tank is not drilled, right? and an overflow box sucks water from the surface and sends it down to the sump. Also, anyone have a recommendation for a good pump for a tank in the 55-70 gallon range? would a 15-20 gal sump be suitable for this size tank? Thanks!

mark

dodge41 · 08-14-2005, 07:35 PM

You are correct about the drilled vs overflow box question. Different ways for different people. I have an overflow box and im switching to a drilled tank. It will be a 70 gallon and I will be using a mag 7 pump for the return. I believe it will be enough but most people believe bigger is better and would recomend a bigger pump. I will be using a 20 gallon aquarium for the sump since I already have one to use. The opinion seems to be the more water the better so the biggest sump you can fit would seem to be the best idea. It seems like you are planning a similar aquarium as I am. Good luck and maybe we can provide valuable info to on another.

Oh by the way- If you go drilled, which I recommend from my experience, get a tank that is drilled. You can do it yourself but most place, if not all, void the warranty on a drilled tank if they didn't do it themselves.

tims · 08-14-2005, 08:13 PM

that is true, if you drill it your self not warrenty.
the sump increases the surface area for gas exchange, and adds stability to the main dispaly over all. as far as the pump size, see what you over flow is going to be rated for. meaning some of the predrilled are 600 ghp , some over hangs are close to that also. you dont want to have apump that is pushing 1000 gph.. you will have a problem soon if you do. if you are going to have the tank drilled, have them put two more holes for a CLS. you can use an external pump and use just about any size.

markak15 · 08-14-2005, 08:17 PM

the CLS is just for water circulation?

tims · 08-14-2005, 08:21 PM

yes , a closed loop system. add a wonderful amount of flow for the tank. it is a totally closed off for the over flow so not leaks or floods. this way you can leave out power heads that can add to the heat of the systems.

AnemicOak · 08-14-2005, 10:49 PM

Here are some sump & CLS links for ya...
http://www.melevsreef.com/what_sump.html

http://www.melevsreef.com/closedloop.html

skeety · 08-16-2005, 07:52 AM

Quote:

Originally Posted by markak15

So let's see if I have this right. The best way to do things is get your tank drilled, which means the water can drain directly out of the tank through this hole, and into the sump. Then it's pumped back to the main tank. The overflow box is for if your tank is not drilled, right?

I want to make sure you're thinking right on this.

Even if your tank is drilled, you STILL need an overflow box. You'd put it around the holes that are drilled. This insures water from the TOP of the column is getting drained down to the sump. It also protects you during power outages/pump failures. It ensures that the water will only drain down to the overflow line.

I wasn't sure with the way you worded that question, if you thought that overflow boxes were ONLY for hang on back set ups, and that if you drilled, you'd just have holes in the bottom of your tank, and that was enough.

markak15 · 08-16-2005, 08:06 AM

so what is the advantage of drilling then if you still need an overflow box? and I'm not sure what you mean by putting the overflow box around the holes that are drilled. i've never actually seen a drilled tank so I'm trying to picture how this is working. thanks for all the info.

skeety · 08-16-2005, 08:40 AM

okay...so you have two holes on the bottom of the tank. (main reason for the bottom, is so that it's easier to plumb the lines into/from your sump.)

Now...if you just leave holes at the bottom, potentially, the entire volume of the tank could drain out those holes.

The point of the overflow box is to block ACCESS (of the water) to those holes on the bottom. The overflow box sections those holes off...so that only water that spills over the top of the overflow box can fall down and drain out the holes. If for some reason, your return pump stops (failure/power outage/etc), then only the amount of water that goes from the top of your water line to the top of the overflow's drain slits/holes will drain down. You make these slits/holes as low as possible without the amount of water that would drain over them being too much for your sump.

Not sure if this makes any sense.

The advantage of pre-drilled overflow over a hang on back overflow, is protection and asthetics (to some).

It looks better (to some), and if for any reason the overflow's syphon breaks on a HOB type of overflow you could potentially have water spilling out over the overflow, on to the floor. If the overflow is IN your tank, it will just spill over into the tank. (note: If the gap between the top of overflow and the top lip of your tank isn't big enough to handle how much water is in teh sump, you can STILL have spillage with a built in overflow to. But there are ways to protect against this..but for now, I won't confuse you any more).

Anyways...I don't know if that helps or not...but if it's close, and you're still confused, please ask more questions.

AnemicOak · 08-16-2005, 09:06 AM

Quote:

Originally Posted by markak15

so what is the advantage of drilling then if you still need an overflow box? and I'm not sure what you mean by putting the overflow box around the holes that are drilled. i've never actually seen a drilled tank so I'm trying to picture how this is working. thanks for all the info.

This might help a little, to go along with Skeety's explanation...
http://www.all-glass.com/products/aq...low_demo.shtml

skeety · 08-16-2005, 09:32 AM

Quote:

Originally Posted by AnemicOak

This might help a little, to go along with Skeety's explanation...
http://www.all-glass.com/products/aq...low_demo.shtml

Perfect!! Thanks for the diagram. hehehe

markak15 · 08-16-2005, 10:12 AM

thanks guys...i got it now.

Flasheart · 08-16-2005, 03:30 PM

1 more comment, you said you were thinking of purchasing a new larger tank. You could just buy a "reef ready" tank which is pre drilled and comes with overflow, and perhaps the overflow kit.

markak15 · 08-16-2005, 08:18 PM

one more question....I'm looking at overflow boxes and some come with this "aqualifter" pump. It says in case of a power outage it restarts the siphon. Is this necessary? I don't see why a power outage would break the siphon. however, if power outages do break siphons, then when the pump comes back on...the tank would flood. any thoughts on this? I don't want to flood my house ;-)

tims · 08-16-2005, 09:39 PM

it all depends on how you have your return line i think.

i will use a non drilled tank as an example.
you have an over flow box with a"U" tube in to to remove water from the tank to the sump, from there it goes to either an internal pump or external pump, then to a return line to feed the tank. If the return line is in the tank below what the overflow box depth is, you can syphn the tank in to the sump via the return line.( untill you raise the return line out of the tank to break the syphon.)
if the return line if at the highest water level( surface) when the power goes out the syphon will brak adn could have an air bubble trapped in the "u" tube. when the power comes back on , unless the air bubble is removed nothing goes to the sump.. but the sump will empty in to the tank and a flood will occur.

i am not 100% postive on predrilled over flows, i am using a HOB over right now but the very future tank has two drilled over flows.. it does not look like there woould b this problem at all with pre drilled tanks and there over flows..but again i am not sure about that part