tank set up question

[Zoa]

Hi....considering setting up a 75 gallon tank that I had set up when I started saltwater....It was a very basic set up--2 1 inch holes drilled in the back......one input and one output. Rubbermaid sump and Ev-180 (now in reef tank). had for a FOWLR. Later moved to a 125--wish I went bigger..sigh.

Anyway, was contemplating setting up the 75 as coral only, no fish. what kind of flow would I want for the tank--4 ft of head pressure? I was also thinking of making more feed tubes that hang over the tank to increase circulation in different areas. or use powerheads. will get another skimmer too. lighting--have 3 x 175 MH. will also set up actinics.

what do you reefers suggest on set up as far as water circulation, etc?

[artful-dodger]

Of course, it will depend upon what corals you plan to keep, but total circulation should be as high as you can get it without flow directed right at any of the corals. 1500-3000 gph wouldn't be unreasonable for corals that need lots of circulation. Some of that flow can be accomodated through the sump, but to get to the high end you'll need to supplement with a closed loop or powerheads.

The holes in the tank back that you described...are either/both enclosed within an overflow box or positioned at the top of the back glass? (If not, you run some risk of the tank draining down to that level and overfilling the sump if you should have a power outage or plumbing leak.) Those holes might best be used for a closed loop.

Do you feel comfortable drilling more holes? If you can possibly avoid using a siphon-based overflow you'll be a lot happier. There are several good threads in the DIY forum on drilling glass and building overflows. Also check the "Horizontal Overflows" thread in the All Things Salty forum. While there, also check out the threads on return manifolds.

If you aren't in a big hurry and you don't consider this 75 exceptionally valuable, drilling and adding overflows are kind of fun projects.

[cmhollis]

What types of corals do you want to keep? If you want to keep SPS, then most people recommend turning over the tank volume at least 30 - 50 times per hour. So for a 75g tank, you would want at least 2250 gph (30x), and try to get 3750 gph (50x) or more. Powerheads are a cheap way to add flow, but I personally don't like the look of things crowding up the tank. So I went with a CLS, and all heaters, etc are in the fuge/sump which is in the basement.

With 4' of head, you could use a Sequence Dart which is a nice quiet pump, and will give about 2800 gph. Here is the pump curve for the Dart:

[Zoa]

ok first I would like to thatnk both artful-dodger and cmhollis for their input. good ideas that sent me looking at other related bulletins.

I would like to start with some softies from my reef....pink leather, shrooms, xenia, and encrusted gorgonia (have a bunch of this now). maybe some of my torch coral depending on growth.

I have 2 1 inch holes drilled in the back of the tank--done by the lfs. I am still familiarizing myself with terms.....so I will say that I think I had a closed loop. water from pump in sump ran into tank. gravity flow let it down back to sump. a durso type box kept water levels up in tank. skimmer sat in sump with dedicated pump. However, I know that the set-up as a whole would not suffice for the corals.

I never used external overflow boxes because I had heard such horror stories. could add a check valve to water drainage area for safety.

I was thinking of using a strong pump, wasn't sure which kind that was strong, 'hearty'(less need for maintenance), and QUIET. I had considered setting tees for multiple pipes to be pressure fed back into the tank in different places. Drilling the tank to do this is always another idea, but I have never done it and would not feel comfy with that as my first tank. I do not think I have the approp. materials at this time. Also, the idea of more holes could lead to more leaks did not excite me. But I agree that powerheads in a tank is not attractive either. Nor will extra lines coming over the tank for water. Therefore, If I go with drilling more holes, how many more would you recommend, and what size?


I read some of the links suggested here...I saw the tanks with the internal overflow boxes. I saw a vendor at Nerac who used a small internal overflow box. Is the primary use of this to maintain a higher water level? what thickness of glass do people seem to like most, and how much area around the drilled hole shoud the internal box cover or take up? what do you find the best in reference to material that binds the glass pieces to one another? I may have to go back to those strands...

Unfortunately, I do not have a basement, fish room, etc....its what I can fit under the cabinet. My 125 reef has a dolphin 3000 ampmaster w/abrasive seals, 30 gal sump, and 20 tall gal refugium that gravity feeds into sump.

so for the 75 gal tank I was hoping to use a tub as a sump, submersible pump, and if I was blessed with any additional room, a small QT tank. or should the QT be separate? If it is separate--as we know the levels are harder to maintain. Or maybe build it in a way that if in use, it can be separated from main tank by ball valves or some other way. Then use a HOB filter for the time in need. I dunno--just a thought as I type here. This is called thinking out loud!

was thinking of the remora pro HOB for this tank as space underneath will be tight.

cmhollis...or anyone else that wishes to add input....what is a CLS. Are both the CLS and Sequence Dart pumps submersible? which one is quieter? Would the Dart pump require extra power for flow? How do these pumps compare to one of the larger mag submersibles? Also, I have not checked out whether its submersible or not, but how quiet is the 'quiet pump?'

in appreciation,
zoa

[cmhollis]

CLS is a Closed Loop System. Basically you have a hole or two in the back of the tank for drains, that is piped to the pump, and then returns to the tank either through more holes in the back or over the top and down into the tank. If you have your returns over the top many people use a spraybar. Do a search on that term, or go to www.melevsreef.com and look at his CLS setup. The Dart is not submersible. It is a VERY quiet, high-flow pump that has a low electrical draw. If you don't want to drill more holes in your tank, then many people use an overflow tube to draw water from the tank to feed the CLS.

Many people have the Dart in their stand right below the tank, and find that it is quiet enough to not be a distraction.

The whole purpose of a CLS is to just jack up the flow in the tank so that you can keep high-flow corals such as SPS's.

If you don't want to go with a CLS, and have a little money to spend, then you might look into Tunze Streams or the new Vortech pumps from Icecap. These are like powerheads on steroids. They go inside the tank and provide an incredible amount of flow, and you can hook them up to a controller to give varying flow, wavemaker functions, etc. The new Vortechs are a little nicer in that the motor stays outside the tank, the pump is on the inside, and they are coupled through the glass magnetically.

A single vortech is rated to somewhere around 3200 gph, which would be more than enough for your tank. The nice thing about the Vortech is that the motor is outside the tank, so it doesn't add any heat to the tank. The Tunze stream is an integral motor/pump so it adds heat to the tank.

Hopefully this gives you some things to think about. The most important thing when starting a new tank is to plan it out down to the last detail so that you don't have to take things apart down the road to make changes. Read, read, read, and read some more. Start out by deciding what you want to keep, and then plan the tank with that in mind. A SPS tank is completely different from a seahorse tank.