Flow decisions for a 120G - Guess I'll turn this into a build thread!

Discussion in 'Equipment' started by anathema, Apr 10, 2011.

  1. anathema

    anathema Guest

    So I've been reading up on closed loops, looking at powerheads online, thinking, measuring, and getting more indecisive the more time I spend thinking about creating a plan for my 120G.

    Where I'm at right now: I have a running 57G rimless with a mag 9.5 and 2 1/2" Sea Swirls. For the 57G, this worked fairly well. I couldn't ever turn the pump all the way up because water would push up the side, and with no trim on the tank it would collect on the rim and drip over. It also tended to dig out the sand in the front corners, but that diminished as the sand aged and settled. I was reasonably happy with this setup, but I would put it right around the minimum amount of flow for that size of tank without having serious dead spots. The major problems I had with this setup is that the vast majority of the flow is pointed straight at the glass, and only hits the corals obliquely. In addition, with the sea swirls, there is no "cumulative" flow effect such as a gyre or circular current.

    This leads me to think I'm going to need more flow in the 120G. I have an extra mag 9.5 I bought on sale as a backup, so in some ways I'd prefer to set something up with what I have. I also very much want to stay away from having powerheads stuck all over the new tank.

    I thought about sticking eductors on the sea swirls and moving to a pressure rated pump, which would help move more water, but would create a stronger jet pointing at the glass and bouncing down it into the sand. Kind of nixing that idea for several reasons, partly because it would add more mass right in plain view on the sea swirls, and partly because I just don't think it's the best solution.

    I then started thinking about using a closed loop. I've never done one, but they seem fairly simple to plan out. However, I wanted to add a wrinkle to mine, in that I was thinking of putting the outlets in the front corners of the tank. I could disguise them by drilling some rock or just sticking it on the outlet with cement until I was happy with the look, and from the front it would look like a normal rock, and eventually I'd grow an encrusting coral on it. Where I'm stuck is in how to aim them, my original idea was to shoot water at the rockwork, from the corners inwards towards the center of the tank. Then I thought maybe a gyre would be better, and then I thought hmm maybe I should just do two closed loops, one gyre on a long on off timer, and one with outlets pointing at the rockwork.

    Which brings me to the problem of finding a pump that can run a closed loop and handle an on off cycle. I was thinking of the gyre being a 3 or 6 hour timer, and would like to go with a fairly short timer on any outlets pointed at the rocks. I know the mag pumps won't work on a timer, they cavitate like crazy on startup. Has anyone done something like this? What were your experiences and do you guys have any suggestions?

    I realize I'm kind of creating a possible tank failure by putting the outlets of the closed loop low in the tank, but I've seen many closed loops with suctions placed low, so I am thinking it's not a huge issue? Any input is appreciated, especially in the planning stages.
  2. Coral reefer

    Coral reefer President

  3. anathema

    anathema Guest

    Yikes that's more than I've spent on the tank, lights, and skimmer combined.
  4. xcaret

    xcaret Supporting Member

    I like the idea of PH free tank, look so clean and closed loops can push some serious flow.
    What kind of tank is it, glass, acrylic?
    I had a Mag 3 on/off on a tank feeding an EV120 skimmer and it went out in less than a year; it was on during the day and I chose to place it on timer at night time.
    I think electronic brush-less pumps can take the on/off better, but am not 100% that they will.
    There's a pump controller, SEIO? I believe it does not turn off the pumps when alternating, rather lower the power on one channel at a time. It is designed for the larger Seio pumps 1100 and up?
    I would have to test it on other pumps, return ones specifically.
    I'm kind of thinking out loud...
  5. rygh

    rygh Supporting Member

    You could consider a closed loop with a SCWD Wavemaker to change the direction.
    Although I believe they have maintenance issues, and probably switch faster than you would like.

    I think the SEIO controller only works with the SEIO powerheads.

    Controllable valves are an option.
    I have yet to see any that are reef safe and do not cost a fortune.
    But it should not be super hard to attach a stepper motor to the shaft of a gate valve.
  6. anathema

    anathema Guest

    Ok Mike. You win, with your well written, persuasive arguments.

    My credit card hurts, and an MP40 on my 57G looks monstrously absurd. I'm also a bit underwhelmed with it at the moment. I had to turn it up almost all the way to kick any sand around.

    At least I don't have to mess around with custom stuff, so my tank will actually get put together in a timely manner. Although, I now have zero budget left for the project.
  7. rygh

    rygh Supporting Member

    2 x MP40
  8. GreshamH

    GreshamH Guest

    MP60... that's what I have for my 4x2x2 :D
  9. anathema

    anathema Guest

    My birthday is in August.
  10. GreshamH

    GreshamH Guest

    Mine is in December but you do not have to wait till my birthday to give me one :D
  11. JAR

    JAR Supporting Member

    Your just procrastinating if you don't get one now.
  12. tuberider

    tuberider Guest

    Maxi-Mods and Tunze Nanostreams.
  13. xcaret

    xcaret Supporting Member

    Good thing he didn't say Tunze 6100 !!

    So besides a CC debt, what else do you need to have the tank running? I have some MJ's with mods that are currently pushing an amazing volume of air in a 5G bucket !!
    Heathers? got you covered; sand, some rock?
  14. Coral reefer

    Coral reefer President

    I majored in persuasive writing
  15. anathema

    anathema Guest

    I need the electrician to come finish the wiring.

    I need enough sand for a DSB in a 120... yikes, that's going to be a bank breaker. I've been meaning to drive to Utah anyway and go snowboarding, I was tentatively thinking of trying to source some of that sand. I used to have contact info for a guy who had oolitic playsand bagged up from the salt lake area, but hmm... that was about 6 years ago.

    I also need to figure out if I'm ripping out those ugly, huge, algae growing, pita oceanic overflows, and if I do that, what to I do with the holes in the tank and which overflow design do I decide to use. I'm leaning towards a plastic back like I did in my current tank, and my 20L and older tanks, and just make the overflow like I did for my 20L, but for a 120 I'm kind of scared to ask how much Tap Plastics is going to charge me for sheets that large. Also, I don't see why I'd need dual overflows at all, as I currently have the same overflow in the 57G and plan on using the same pump for a return. I get more space if I cut one out, but then I have holes to patch, or holes to put a closed loop in that I seal up and don't use but have for later if I decide I want it.

    I was originally thinking I would make a center overflow, and since it has 4 holes across the bottom panel along the back wall, I was planning to use the outer two for a closed loop outlet or two, and use the inner two for the center overflow/closed loop intake. Now, however, I am very tempted to just cut one of the overflows out, patch the hole with some spare glass and call it a day. I'd sure feel dumb if I decide I need a closed loop later though and I patched the holes and buried them.

    Also, I need to decide on a salt mix. Scary. This tank is unfortunately large enough that the effort of lugging the amount of water I'd need from a fish store to my tank becomes both uneconomical and too much work. Considering I was threatened with arrest for collecting water from pillar point marina, I'm not that much into collecting my own either. I sure will miss NSW. I don't look forward to losing corals to mixwater.

    So basically I need to find sand and make a lot of decisions. I do know that I want to use a clean substrate, not old stuff. Whether I just rinse something really well, or buy a commercial bagged product. I reused sand that I had stored in buckets for my current tank, and I think it's about time for a new, clean pile of sand. I also have some cc I got from the steinhart, which I could give an acid bath and try a shallow layer of that. Tempting because I think it's better for fungiids, but scary because I've had two cc tanks in the past, long long ago, and they were both disasters. One was in 1995 and one was a few years later though, and things have come a long way since then. Decisions decisions... It's very difficult to feel good about changing something that works so well for me and my personal style of reefkeeping, even when I read other people's convincing stories.

    I'm all set for rock. One of the biggest hassles of this whole project is that I have a 50G plastic barrel of live rock that is "cooking" and has been "cooking" almost 5 years now. It's pretty dead heh, but it's impossible to move without filling a new barrel with water and transferring it piece by piece. It's currently right in the middle of where the tank is going to go. Of course. :p I wish I had a barrel dolly...

    I don't actually plan to add more than 1 or 2 more pieces of rock to the layout I had in the 57G. I've always wished it was more spread out, now's my chance.

    Guess it's my turn to think out loud... time for bed!
  16. xcaret

    xcaret Supporting Member

    2:27am Time for bed? is almost time to get up from bed !

    Well, I have some sand, was rinsed and Sun-dried before placed in a container.
    About the overflow walls, if you decide to take those off LMK I can give a home to one at least, probably will end up stored away.
    For the pre-drilled holes, you can use bulkheads and plug them with PVC, a short piece, under the tank a ball valve; since they are in the back, a PVC sticking a little bit above the sand bed so you can unplug and use a closed loop if you decide to.

    I have a Brute container and got a wheeled-base for it, is currently full with SW for the next WC but can be emptied pretty fast then mix a new batch

    Although I'm scared to death of electricity I can check what has to be done.
  17. Joost_

    Joost_ Guest

  18. anathema

    anathema Guest

    Thanks Joost and Mario!

    I'll let you know if I take out one of those overflows or both, I'll try not to break it. I don't recommend them though, these ones are cut out for more flow and a bit ugly looking, whoever had this 120G must have tried to turn over their tank 50X an hour. I don't like the one in my 57G at all. It's really quiet, but it grows bubble algae in between the panels and it's impossible to clean it out. Sheds free floating bubbles into the tank now and then. I really think I prefer a normal slotted overflow, I've had pretty good luck getting those to be close to silent.

    I used my last bag of southdown for the 57, I think I bought 10 or so when BARE did a group buy of a pallet of the stuff. Tank calculator says I need 6 bags or so, seems like a lot to me, I only used 4 bags setting up my old 200G-4 compartment system with a DSB, remote DSB, and a refugium with a DSB iirc. There is a hardware store in Arkansas that has it for $3 a bag, but shipping is $189. Still might be the cheapest option.

    How much do you want for your sand Mario?

    I don't mind the color of the Utah sand, but it seems like those phosphates might be an issue. Considering gas prices are so high, it's making me not feel like driving there so much anyway. Kind of missed the good snow with health issues this last month.
  19. Joost_

    Joost_ Guest

    As flow goes, I'd vote for the mp40 too, however, another much cheaper option would be to get the cheap ebay power heads. yes they're ugly, yes they're huge, yes they're crappy quality. BUT they move some serious flow for the price, at 35 bucks for 3600gph (IIRC) they're quite a deal. You can always update to a mp40 down the road.
  20. xcaret

    xcaret Supporting Member

    How about a Nickel?, that's right an all-mighty 5/100 of a dollar !!

Share This Page