Tank Turn Over with Ocean Water

[Kharn]

Hello

Hope I post this in the right area but it does seem like a rather chemical related question...

I have the opportunity to build a system literally "meters" from the ocean where the water out front is very clean and lays host to countless SPS corals and fish etc.

My question is I want to run the system off the ocean basically by pumping the water from the sea out front through a simple filter system then into the tank(s) I have planned.

However in such a system my plan was to have no filtration except for the minor mechanical filtration between ocean to tank (swapped/cleaned daily) and then actual powerheads in the tank for flow (sunlight is the light).

But my main point is this, how many times per day would it be smart to have the pump running from ocean to tank, how many times should the water volume be turned over daily, if at each turn over it is fresh new reef water?

 

[twon8]

As many times as you can would be best, then you don't have to worry about alk/ca levels dropping

 

[Kharn]

As many times as you can would be best, then you don't have to worry about alk/ca levels dropping

The general theory I'm rolling with so far is 1/4 system volume per hour.

 

[bertoni]

That's an interesting question, but I don't know the answer. One parameter to consider is the volume of fish in the system. They will produce a lot more ammonia in the water column than most other animals we tend to keep. ¼ of the system volume per hour sounds like a great starting point, and I'd be surprised if you needed more than that, but I could easily be wrong.

 

[bbaz123456]

I don't know the answer either, but would it be that hard to just run a small pump constantly and overflow right back? A 150 gph pump would only cost pennies to run...although I am not sure how much head pressure you would have, or what size tank you plan on having. IMO you would be better off with a smaller pump that runs constantly than a larger one that would cycle on and off.

 

[billsreef]

With some filtration on the tank, I'd suggest around 10% per day. Without, I'd looking at least 7 times total system volume per day. IMO a filter system that can be self sustaining without any water exchange would be ideal, as that way your tank will fine if your SW system fails for any reason. Give you a bit of breathing room to deal with those inevitable problems, and you can still have the benefits of substantial NSW water flow.

 

[Reefvet]

Besides water what's going to be in the tank ?

 

[Reefvet]

Oh and one more question. How far are you from any source of agricultural runoff ?

 

[ichthyogeek]

Umm...just to point this out, but aren't you worried about disease? Here in the states, a lot of the big stores sell their fish in bags that specifically say not to release into the wild. There's a pleco problem in Florida, and Lionfish in the Gulf. People catch Pacu seasonally. Disease organisms would be constantly flowing in and out, both introduced into the tank by the fish and inverts you plan on adding, and from the ocean itself...Not to mention the live rock. Unless you plan on using only fish, live rock, and inverts that you collect from this area around you. Then it sounds fine.

How would you deal with evaporation, as well as the initial water filling? Would you be filling the tank with synthetic seawater? Or natural water from the sea?

Also, how would you medicate this tank? By replacing the water with natural seawater, you would be adding medicine to the environment, which could adversely affect the surrounding wildlife.

 

[nemodan]

Some years ago I saw in a TV program a house in Hawaii built nearby a cliff. The owner was pumping 24/7 water from the ocean to a gigantic tank in the basement. The water was returning by a small artificial canal built from the house to the cliff. It was just going back to ocean by gravity, not pumped.

The tank was like the ones in public aquariums with literally a couple hundred tropical fish from the area. Lots of yellow Tangs, for example.

The owner explained that due to the continue circulation of the water he was able to keep such bioload.

The pump was far away from the cliff, to pump clean water.

The tank was part of the house, not a classical glass Box. The pump was working all day and he has some backup system, but can't remember now.

 

[billsreef]

Icthyogeek raises some important points that I didn't think to get into last night.

On the effluent side, what are you planning on doing with all that waste water? If you only keep locally collected livestock (including any live rock and sand), than you'll be alright with just discharge back in the sea (check on any local permitting requirements, usually necessary for discharge most places...sometimes also for the intake). If you keep anything purchased from an LFS, than absolutely no discharge to the sea without a well maintained and very good sterilization system on the effluent to prevent any introductions of pathogens or other species from elsewhere.

The intake side also has it's issues. Raw water (what we call the SW direct from the ocean without filtration) will be loaded with plankton...both good and bad. This can introduce disease organsims, as well as larval stages of predators such as crabs. This also will bring in phytoplankton, copepods and other beneficial organisms. Bit of dice rolling going on with raw water. Filtering down to 10 microns will remove most of the larger stuff such as crab zoea, but still leave phytoplankton and various protozoans, including disease causing protozoans. Using a sand filter to get the large stuff, follow with a 5 micron cartridge filter and large UV will give you well filter sterile water...though any lapse in maintenance of the filtration can let some surprises through on occasion. You really need to weigh the pros and cons. Also do your SW plumbing such that you can readily run a "pig" through the piping to clean it out of fouling organisms...you will get barnacles, clams and such growing in the plumbing A few more things to consider, but this is likely enough for now.

 

[CuzzA]

On my newest build I will be using NSW. My plan is to collect water once a month at one of my local passes at the incoming/high tide during the middle of the week (less boats/people) while remaining conscience of rain, etc. I'll pump the water through a 10 micron filter bag into a 100 gallon poly transport container and then transfer it to a stationary storage container for filtration. This tank will be as closed as tight as possible to reduce evaporation, yet still be able to vent. The filtration will be 1 Magnum 350 filter. This filter is unique in that ALL the water that goes through it is filtered. There is no bypass. Because of this design I'll be able to use DE powder in conjunction with the cartridge filter which will filter down to 1 micron. I'll run this for 24 hours before removing the DE powder. This filter also allows the use of carbon concurrently with the other filter. So 2 birds with 1 stone. I'll replace the carbon with every collection.

Finally, I have an Emperor Aquatics 80w High Output UV. This will run 24/7 with the intake water coming directly from the Magnum filter. Also I will set up my auto water changer (3 gallons per day) so that a solenoid will open off the UV and replace the 3 gallons removed from a separate pump. I'll use my current Apex conductivity probe to monitor the salinity in the container and top off manually if needed.

I know this is a little different than what you doing, however, you can get the idea of the lengths I'm going to go to to insure that the water entering my system is pure, clean saltwater. Most public Aquariums near a coast that use NSW filter the water before letting it come into contact with their systems.

 

[Bilk]

I believe some public aquariums use water directly pumped from local waters. However I also believe this water passes through a diatom filter before being introduced to the system tanks, to prevent introduction of unwanted organisms.

This idea of yours would at first appear to be ideal, but as Bill already pointed out, if there was an issue with the water change pumps, there would be a problem in the tank. Adding some live rock to the sump and or tank would certainly give you time to get it functioning again and having a reserve reservoir is probably prudent.

 

[polleke]

Well if acros grow in that same water it should be fine for anything you want to keep indeed.

What was mentioned already is imo more important. Are you going to introduce non native species (fish, coral, algae, inverts, live rock) to your tank? I would be extremely careful with the return water. Definitely not just pour back into the ocean.

 

[Kharn]

Sorry for asking and ditching I lost / forgot about the thread but the question remains important to me and I highly appreciate the responses.

Everything in the tanks is going to be locally caught and everything to do with the tanks is going to be locally made, I do not have the luxury of "LFS" where I am located...O_O! (as in nothing would make the journey from any "close" LFS/Airport), so it MUST be local in that sense.

Everything I want to keep I have seen in the water that I intend to use.

As of right now I am more inclined to go the simplest route possible and work up from there, specifically when it comes to filtration & lighting.

"Biggest" case scenario I'll be looking at possible 13 tanks total.

5 @ 2000mm L x 1000mm W x 500mm H @ 1000L each (SPS, LPS, POLYP, FISH, INVERT).
4 @ 2000mm L x 300mm W x 900mm H @ 200L each (Stomatopods).
4 @ 2000mm L x 450mm W x 600mm H @ 300L each (Stomatopods).
7000L Total

From what I have gathered 'math' wise I figured off the total volumes the following total turn over figures @ LPM&LPH (liters per minute & liters per hour).

7000L Total - RED indicates likely choice.
(@x100 24hrs CONSTANT)
700,000L over 24hrs = 29,166.666lph
700,000L over 1,440mins = 486.11lpm

(@x50 24hrs CONSTANT)
350,000L over 24hrs = 14,583.333lph
350,000L over 1,440mins = 243.055lpm

(@x10 24hrs CONSTANT)
70,000L over 24hrs = 2,916.666lph
70,000L over 1,440mins = 48.611lpm

(@x5 24hrs CONSTANT)
35,000L over 24hrs = 1,458.333lph
35,000L over 1,440mins = 24.305lpm

(@x1 24hrs CONSTANT)
7,000L over 24hrs = 0.291lph
7,000L over 1,440mins = 4.861lpm

The general idea was to utilize the ocean as much as possible due to its sheer proximity and well it being the ocean along with the bounty of already living marine life 2-3mtrs off the beach itself.

Commercial, Agriculture all that stuff is none existent, the neighbors are a tribe lol... however the only thing that does turn the water bad is heavy rain fall and it can turn the water a muddy brown for "X" hours, depending how often it rains (this is what freaks me out the most).

 

[Kharn]

Filtration planned FOR STARTERS (which I will diverse off from there if required), is going to be a simple (but checked bi/tri+ daily) dual filter sock system, where fresh ocean water first passes a larger micron sock before passing through a small micron sock, before finally entering the tank, again these socks will be checked bi/tri+ daily with more then enough ready on hand fresh, idea for them is simple, 2 in use, 2 in cleaning/drying, 2 clean/dry/ready and 2 spare all of each size.

 

[Kharn]

There will always be flow within the tanks 24/7 (whether turnover water or same water), this will be achieved through powerhead/wavemakers, I'm looking into the Gyrespect XF170 for the 5x1000L uniform tanks.

All I'm trying to do is nail down the best 'ocean' pump for both system & wallet. =)

 

[billsreef]

however the only thing that does turn the water bad is heavy rain fall and it can turn the water a muddy brown for "X" hours, depending how often it rains (this is what freaks me out the most).

Two ways to deal with this that I would recommend, both involve turning off your raw water system. One, large back up water storage reservoir to provide clean water while your waiting for that worst of the storm muck to clear. Two, filtered tanks that will be adequate to run without water exchange for long enough for the water to clear enough.

Filtration planned FOR STARTERS (which I will diverse off from there if required), is going to be a simple (but checked bi/tri+ daily) dual filter sock system, where fresh ocean water first passes a larger micron sock before passing through a small micron sock, before finally entering the tank, again these socks will be checked bi/tri+ daily with more then enough ready on hand fresh, idea for them is simple, 2 in use, 2 in cleaning/drying, 2 clean/dry/ready and 2 spare all of each size.

The first set of sock filters are going to be high maintenance. I'd suggest running a swimming pool style sand filter as the initial filter. Maintenance is a simple backflush, as opposed to cleaning/replacing filter socks frequently.

All I'm trying to do is nail down the best 'ocean' pump for both system & wallet. =)

You need to consider how much suction lift you need, as well as head pressure to work your needed pump size. Suction being the real critical one, pumps just don't like to pull well. So the closer to the water source, both in distance and height, the cheaper the pump you'll be able to use.

 

[FraggledRock]

SO basically he is collecting wild fish and Wild corals?

Has it not dawned on anybody that this may be a conflicting decision in regards to this thread?:
http://www.reefcentral.com/forums/showthread.php?t=2476256

I know it would just make sense to go dive grab some corals and fish and put them in a tank.

BUTTT isnt that the reason "conversationalists" are pushing the intended bans and laws against aquaculturing/coral farming in preserving the reefs? to prevent humans from going into the wild and scooping out whatever they want?

 

[woodnaquanut]

SO basically he is collecting wild fish and Wild corals?

Has it not dawned on anybody that this may be a conflicting decision in regards to this thread?:
http://www.reefcentral.com/forums/showthread.php?t=2476256

I know it would just make sense to go dive grab some corals and fish and put them in a tank.

BUTTT isnt that the reason "conversationalists" are pushing the intended bans and laws against aquaculturing/coral farming in preserving the reefs? to prevent humans from going into the wild and scooping out whatever they want?

I'm guessing you meant conSERvation.

Since the OP is in the land of OZ, our U.S. laws have no effect. I don't see how this is on topic to the OPs questions about flow and possible system setup.