To Drillith, or not to Drillith...

[nine9d]

Hey everyone,
Well I think that with the talk of my thread about circulation without powerheads (http://archive.reefcentral.com/forums/showthread.php?s=&threadid=291010) was a good one. I am going to use 2 SCWD's for water movement and I have a couple of questions on getting my tank drilled and setup. Below there is a pic of what I was thinking to do.

1). I want to drill 3 holes in the back and 1 in each side. Is that too many holes?

2). Is there anything that I should be concerned about and/or do different in my setup below?

3). Is there any location to place the holes or size of hole that I should go with or avoid?

I have a CL on the back with the 1 return and 2 outs. The returns coming up the sides is from the sump that will also be connected to a SCWD. What do you think?
http://www.hvreef.org/members/nine9d/images/holes.gif

Thanks once again guys.

[andro]

Hey Ross nice diagram.

You will get a lot of water flow from that.

One problem though is the returns from the sump thru the glass, you are going to have to make sure that during a power outage or when you turn your pumps off, that your tank does not drain out to the level of the holes. I would recommend putting the returns over the side of the tank.

For the closed loop it should not be a problem to have the returns thru the glass. To make it cheaper for you (not as mant drilled holes) you could put those returns over the top also.

Just my $.02


I attached my original plans for a closed loop that I never ended up going with at the time due to lack of funds.

http://hvreef.org/members/andro/images/Tank%20Plumbing%20Closed%20Loop.jpg

-Ian

[skearse]

Looks good. My only though would be to move the CL in line to the opposite side from the overflow-the bottom right corner above, to help make sure that water throughout the tank is getting moved around.

[nine9d]

Thanks for the info guys. I could do that with the pvc for the returns, but how close can I drill the holes to the top of the tank for the returns? That would help in case of a power outage. Also, I hope to be getting a generator for the house this summer. Whoo Hoo!

[andro]

I think 2" below the edge is OK, thats what mine are, or maybe they are 3", now I don't remember :p


-Ian

[ChrisRD]

I would also be cautious of putting a bulkhead too low in the tank (unless it's inside an overflow box). If you have a problem with a leaking bulkhead/nearby fitting someday (probably unlikely, but I'm paranoid) you could potentially have to drain the tank below that level to replace it.

[Reelfish]

I would not put any holes lower than 1-2" in the tank. You can use all kinds of attachments to change the direction of flow. Lower holes tend to siphon the water back to your sump and unless you have a large one it will overflow. I also would not want the holes below the top of the rock because when the water is siphoned out it exposes the rock or worse the corals on top.
Bob

[masterswimmer]

I agree with Bob (reelfish) and Ian. Holes too low can only be a problem. We've got enough ways to circumvent the necessity to drill low. Head off the problem before it occurs.

Russ

[nine9d]

O.k. Thanks a lot guys. I have a 49 gallon sump just so you know. That is why I asked for help becase I need your help :) So anything lower that 2" can be problematic. So I guess maybe I can run the returns over the top like Ian suggested and get a couple drilled about 2" from the top. Does anyone disagree with that statement? OR should I go like my last thread and do the pvc? I thought you guys were against that pvc method?

[masterswimmer]

I'm not a big fan of PVC. Doesn't allow for even minor adjustments. Flex PVC wouldn't be bad though. The best of both worlds IMO.

Russ

[Reelfish]

The standard over the top return lines are lower in the tank then your overflows are and the tank will siphon to that point. If you drill a little hole in the return line about the same height as the overflows you can prevent that.
Bob

[masterswimmer]

Originally posted by Reelfish
The standard over the top return lines are lower in the tank then your overflows are and the tank will siphon to that point. If you drill a little hole in the return line about the same height as the overflows you can prevent that.
Bob

Excellent point Bob, a siphon break.

Russ

[Indy1]

I've drilled siphon breaks right at normal water level. It breaks the siphon almost immediately in a power outage. Less water draining back to the sump, less worries.

[masterswimmer]

Originally posted by Indy1
I've drilled siphon breaks right at normal water level. It breaks the siphon almost immediately in a power outage. Less water draining back to the sump, less worries.

Drilling the siphon break right at normal water level is cutting it too close IMO. If you are away for a few days, normal evaporation (with no auto top off) could activate the siphon break unnecessarily. Just a 1/2" or even an 1" below the surface, providing your sump has the capacity to hold that much backflow, would work better. It's not difficult to calculate how much backflow would be involved with 1/2" or 1" below the surface.

Russ

[nine9d]

Everytime I look at this thread my head starts to hurt. The more and more I decide how to do things, it seems the more and more I should change it. ARGH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[ChrisRD]

Originally posted by masterswimmer
Drilling the siphon break right at normal water level is cutting it too close IMO. If you are away for a few days, normal evaporation (with no auto top off) could activate the siphon break unnecessarily. Just a 1/2" or even an 1" below the surface, providing your sump has the capacity to hold that much backflow, would work better. It's not difficult to calculate how much backflow would be involved with 1/2" or 1" below the surface.

Keep in mind you're talking about return lines here - there's no siphon to break unless the return pump is off. In other words, while your return pump is running, having the water line dip below the anti-siphon hole really isn't a big deal. You'll just see a little stream of water squirting out of the hole.

[seaham358]

Ross your never going to get the tank set up, Just go with what you want to do and fix any problems that come up.
Go with what you want to do and what follow the advice you get from experienced reefers who have tried and learned from there mistakes.
Don't second guess yourself....

Your plan sounds good just to it!!!!
The more you think and plan the more complicated your making it for yourself. No matter what you do you will wish you did something different.
It's time to set it up and fill that puppy with water.

[nine9d]

I hear you Bob. That has to be one of my biggest downfalls. I really, really, like to have everything planned out and right the first time. I really hate error. Especially if it is something that I should have known before I did something. I just have to do what I want and pay the price later. :(

[ChrisRD]

I agree with Bob, no matter how many tanks you setup it seems like you always find something you'd like to do different next time. It's good to plan things out well, but don't agonize over every little detail and stress yourself out. This is supposed to be fun afterall...LOL

When in doubt go with the simpler solution. And keep in mind that you can make changes and upgrades later if you want to tweak something (which you WILL ;) )

[skearse]

Ditto with Chris & Bob-I'm already wokring on redoing my return system (for the third time) since I set the tank up (last August!) To this end, I like using the over-the-wall method for the returns b/c I am not locked into having to pipe to a certain point on the tank.

As far as the PVC goes, I used rigid PVC for almost everything, but Russ is right, it can be tricky getting the measurements to line up. I also went with glued fittings, because IME threads will ALWAYS leak, no matter how much dope & Teflon tape you use. The obvious downside to this is that when I change things, I end up reworking entire sections, b/c I don't have anywhere that it's convenient to disconnect (I do have unions on all the lines, though, so it's mostly not that bad). And, of course, this costs a little more also.

JUST some pros & cons that I have already found-but most off all, just do it & get it started!!!!

[madmike]

hey ross, I purchased my 90 with all of the holes already drilled from a previous owner, but I like the flow they create in the tank using a squid and the sea swirls, totally random flow when I put stuff in like food for the fish, flows every which way. My tank is 24" deep though, so it was alot easier to hide all of the loc-line behind and through the rockwork, I will post a pic tomorrow of the rock in the tank if I get time.
Mike

[nine9d]

Thanks mike looking forward to seeing some pics.

[madmike]

finally got some time to take a pic of the new tank, been up about 2 weeks now.
Mike
http://reefcentral.com/gallery/data/500/19961after.jpg

[madmike]

here are the pics of the plumbing you requested...what can be seen.
http://reefcentral.com/gallery/data/500/19961plum3.jpg
http://reefcentral.com/gallery/data/500/19961plum2.jpg
http://reefcentral.com/gallery/data/500/19961plum1.jpg