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StirCrazy
11-20-2001, 10:43 PM
I was trying to sleep last night and a thought came to me.. (what a time to get a thought images/smiles/icon_smile.gif ) anyways.. what I was wondering is instead of the chaotic water motion we are trying to get.. would it maby be better to simulate the tide instead of the waves? I mean have the curent go one direction in the tank for about 5 hours then almost stop for 1 hour then switch directions for 5 hours.. and so on.. would simulate the 6 hour cycle of the tide during the one hour you could have some sort of real soft curent going (haven't totaly figured that out yet) but I was wondering if anyone else has thought about this and tried it.


Steve

Reefmaster
11-20-2001, 10:47 PM
hey steve
there is very little tidal action in the tropics. most of the current / water movement is due to surge action from the waves, and when diving it is really wierd cuz ya move one way for about 10-15s at a pretty good clip, then slow, stop, and right back where ya came from. the ideal wavewaker imo is some sort of surge device. if only i had more time....

Troy F
11-20-2001, 10:56 PM
Check Robert's return set up:
Waterflow (http://avdil.gtri.gatech.edu/RCM/RCM/MICHELSONAquarium.html) , it isn't exactly what you are talking about but could be given a longer cycle.

Here is another product that gives a more natural wave approach:
Wave2k (http://www.wave2k.com/product.htm) .

If you could trust timers you could run two different return pumps, each plumbed to a different end of the tank.

[ 20 November 2001: Message edited by: Troy F ]

StirCrazy
11-20-2001, 11:51 PM
Hey Troy thanks, I like Robert's return set up, and it wouldent be to hard to gear it down so it was at 1/2 rpm or even 1/4 rpm, definatly something for me to look at ..

Steve

[ 21 November 2001: Message edited by: StirCrazy ]

Silverfish
11-21-2001, 12:08 AM
Hey Steve, I have been thinking about the tidal movement thing too. Check out ozreef.org and scroll down to Water Circulation System. Seems like it could work, if you don't mind having a tall hood! I think that the tidal movement, together with random turbulence (wavemaker w/ powerheads?) would be ok. What I would really like to build is a surge device like Eric Borneman has in his book, Aquarium Corals. I have bought the toilet flush valve already, just have to put it together! ($8 @ HD) images/smiles/icon_cool.gif I do like the idea of getting rid of the powerheads in my tank tho.
Later, Bruce

StirCrazy
11-21-2001, 07:18 AM
hey Bruce .. I have been thinking of how to make the water ove for a while.. I have decided I don't want splashing around on the top but I just want a gentle change in directions (this way I don't have to worry about splashing water out of the tank images/smiles/icon_smile.gif )
this rotating valve has my intrest as I could make the valve body out of pcv, and I am sure we have a piece of teflon I could chuck up in a layth and make the valve body.
which brings up anothr thing.. is teflon ok in a tank?

Steve

Acro
11-21-2001, 08:50 AM
hey bruce ya should have told be got a toilet thingy here would have giving it to ya I have done everything from the carlson surge to wave timers now seaswirls and something that no doubt is very important is water flow the surge bucket I had was very good but loud and lots a bubbles but I loved it and did the corals so the flange thing is supposed to be better I just got tired of playing with it and ended up in the rubbermaid with all the other projects.I would also like something that would kick the s$%# out of everything but only say half a dosen times though out the day hey the surge bucket I had before was a 13 gallon garbage bucket on the top of my tank taryn just loved it I got a picture of it I'll scan it in later
jamie

Acro
11-21-2001, 09:32 AM
couple of the thinks to remember about surge devices are can your over flow handle the extra volume and can you sump flucate that much

[ 21 November 2001: Message edited by: Jamie Cross ]

reefburnaby
11-21-2001, 10:33 AM
Teflon is safe for reef use.

- Victor.

StirCrazy
11-21-2001, 06:06 PM
Well I got a e-mail back from Robert C. Michelson, and as I assumed he built the guts out of Delrin rod and used a interferance fit (with teflon) to seal the end gland. this will not be that hard to build but as I am unfamilier with Dlrin rod I will have to check up on it and see what the differences between it and something like teflon or nylon is.. the later two I have access to in abundence.. the only other think I need to find out is whare I can find a "synchronous 60 Hz AC clock motor" any Ideas?

Steve

Troy F
11-21-2001, 08:08 PM
Shane, I was thinking about what you said about "very little tidal action in the tropics" and would like that clarified if possible. I've not been anywhere tropical myself but do have an understanding about the tidal dynamics and it would seem to me that location would dictate how high the tide would be. I would guess that a lagoonal reef may even get more water motion from tidal action. Did you dive a forereef? I'm a little envious. There is a guy on www.thereeftank.com (http://www.thereeftank.com) that just got back from the Indo-Pacific, hopefully he's going to send me a copy of his dive video.

DJ88
11-21-2001, 08:42 PM
Shane,

can you clarify the tidal action for me as well. I know that when I was in Australia and anywhere else there is still tides. The hieght of the tidal action depends on several factors but it is there. You won't feel it unless you are in an area where that flow is restricted. Or where the shape of the land dictates and even higher tidal action than normal. ie. Fundy and the St Lawrence. In open water you probably won't feel it persay. The wave action will be what you feel. It is so much stronger than a tidal action. Thus would cancel the feeling or perception of the tidal movement out. Or if the tide was moving in the same direction would add to the wave action. Same ideas as any wave interferance patterns. images/smiles/icon_smile.gif

To me a device creating tidal action is a good idea. But in our hobby I dont know how realistic or feasable it is. Our powerheads or sea swirls will counteract any slow tidal motion we do create moving from one side to another.

That is from what I have learned about tidal actions tho. And some experience from bobbing on the open ocean.. images/smiles/icon_wink.gif

[ 21 November 2001: Message edited by: DJ88 ]

StirCrazy
11-21-2001, 10:47 PM
but Darren thats the idea.. if I make a tidal system then i don't need power heads in the tank and the tiday will be controled by one pump. (thats why I am going to give making this valve a try at work) it doesent seam hard at all to do. And if I make a rack for my live rock I could maby have a small power head pumping into that and have a slight curent pushing out from under the rocks. I was going to start making it tomorrow but I am having knee surgery on friday so I will put it off for a couple weeks.
about the tropical tides.. yes there are tides about 12 foot tide in Hawaii (been there over 20 times) and in Hanuma *sp bay there is a alternating curent that when you are diving moves you about 10 to 15 feet in one direction and then back again.. and the small reef that is 4 to 5 feet out of the water at low tide is about 4 or 5 feet under water at high tide.
it wasn't the hight of the tide I wanted to replacate it was the predomanant direction of flow during the tides..

Steve

Silverfish
11-21-2001, 10:58 PM
Hey Steve, what type of reef are you setting up? SPS, softies, mixed?

StirCrazy
11-21-2001, 11:24 PM
well what I have decided so far.. I Live rock tank images/smiles/icon_biggrin.gif seriously.. it will be a while befor I can do sps I figure I will start off with easy stuff till I get the tank going how I want it ..I might put a fish in there : ) I think the muchrooms and pulsing xena are real nice as well as other softies I have been seeing laitly sooo..

Steve
P.S Bruce, you have to get a web site going so I can see your tank images/smiles/icon_smile.gif

[ 21 November 2001: Message edited by: StirCrazy ]

Silverfish
11-21-2001, 11:33 PM
Sorry man, I can type(sort of), point and click, and that's about it. I'm computer illiterate, you'll have to see it in the flesh images/smiles/icon_biggrin.gif ,,
unless Adam posts some pics for me.. he took some today images/smiles/icon_cool.gif

StirCrazy
11-21-2001, 11:42 PM
haha no problem.. I have a digital camera also if you even need some pic taken and can't get ahold of Adam

I am having knee surgery on friday so I won't take ya up on that right away but soon hehe

Steve

Silverfish
11-21-2001, 11:52 PM
Cool! images/smiles/icon_biggrin.gif

DJ88
11-22-2001, 12:04 AM
Hey steve.. there are devices out there for doing surges.. Is that what you are looking for?

If you are trying to recreate the flow on a reef keep this in mind. You would have to have a flow of 48,000 gallons per hour in a 100 gallon tank. Something we can't attain in a tank.. You are talking about massive pumps there. We can get 2400 GPH pumps. but a problem with having that blasting out of a nozzle in your tank is that it isn't good for your corals to be hit with such force. I have had a coral's tissue recede when a maxijet fell and blasted it for too long. It took a fair amount of time for it to recover. Most won't.

Tides aren't really water movement like most people think.. It is the ocean rising and falling.. That is it.. it is the waves and currents that you feel when diving and what gives the corals the nutrients they need. To me, when you say tidal action you are talking about raising and lowering the water level in your tank to mimic the action you see on shore. If you want to have water flow you are talking about currents and wave action created by the winds(which we try to create with powerheads and pumps), semantics I know.. But those are what tides and currents are. Tidal surges you see in a harbour or on the beach are caused by the water moving up along a shoreline or a channel. When we were out at sea we never saw the tides moving and changing. We didn't have a reference point. On a reef the rising and falling of the tides isn't perceptible. But currents created by wave and wind action are.

One of the reasons for having the wave action and circulation in the tank is for aiding in the removal of wastes to the sump and then the skimmer. Without this higher flow it(wastes) will deposit itself on the rocks and break down in your tank. Which we really don't want. Too many wastes breaking down can lead to algae, cyano and can cause different problems with corals if it builds up on the corals and isn't removed. RTN is one of these, receeding of coral tissue is another. No growth at all is another possibility

The higher flow and random flow helps bring nutrients to the corals. Phyto, minerals etc. Calcium. By lowering this flow you may not replenish the needed or desired nutrients..

IMO, I find the best growth appears on corals in a tank with water flow from a sea swirl. Cycling power heads on and off is another cheaper option. Closed loops sytems area n added bonus and I am concidering it with my 120 when it is built. Those are the options I will chose to use.

If you can stand the noise and the equipment go for a surge device. They do a great job of mimicing the wave action you feel on a reef. Tho they can get blocked up, fail and may overflow or worse.. A new design out there but still not for sale as far as I know is the Wave 2K. Great idea but many moving parts. more parts means better chance of failure.. And with a DSB you will get buildup of detrius and sand in the mechanism. The mechanisms inside that thing for the most part are nylon.. They will wear out fast with sand or crap rubbing in the threads.

I am gathering you want a constant flow in one direction for a specific period of time. then reverses itself. I think the best description of what you want to build is the closed loop circulation system I mentioned. One that alternates. That alone is a good system but to me adding in the random actions the powerheads or other devices add a bit more to the picture. To have that flow you fel in the ocean you would need to have the whole side of your tank as one huge outlet for a pump. Otherwise you will only get the flow you desire for the first few inches out of the outlet.. Then it is sent in all directions. Even then if you didn't have the same huge opening on the other side you woudl not get an even flow. You will get it coming into the tank from one 2 inch opening(assuming 2") and then exiting out another similar opening on the other side.. With that you won't get the flow you desire throughout the tank. For the most part only between the two outlets/intakes. If you have only that you will end up with areas where there is no circulation or turnover of the water. Dead ares in effect.

We are doing the best we can to re-create something we can't possibly provide. that massive water flow you feel on the reef.

IMHO...

[ 21 November 2001: Message edited by: DJ88 ]

reefburnaby
11-22-2001, 12:41 AM
Steve,

Low RPM motor ... how about one of those BBQ rotsiere motors. Or how about a stepper motor images/smiles/icon_smile.gif

Another alternative for water circulation is using one of those plastic water sprinklers ... the one that was three heads and they turn round and round. Don't know how well they work...but some reefers are using it.

- Victor.

Reefmaster
11-22-2001, 11:58 PM
troy and others
i don't remember the details but will look em up in my coastal engineering text from uni. what i remember from school is the moons gravitational pull is less so at the equator and more so towards the poles. will have to look to see if thats cuz the volume or mass of water is so much greater towards the poles. i've dove hawaii and they do have tidal exchanges, but cancun and bali for ex have very little tide. of course ther is still some, but not like what we get out by tofino! in the tropics i think the driving force for currents is wave action which results in surge hence all the surge devices. otherwise we would just run our pumps from one side of the tank for 6 hrs, then switch em up. thats exactly what we have on the west coast, especially places like quadra island, current moves up to 10 knots in one direction, then switches 6 hrs later. but i'll check on why i didn't think they had much for tides in the equatorial areas. as for diving i have dove the foreshore reef of cozumel and some of the lagoonal areas of cancun / play del carmen. as well as hawaii where i saw a 5' reef shark!

Troy F
11-23-2001, 04:35 AM
Well, I picked up AFM's new issue and low and behold, an article on water movement by Ron Shimek. I see Darren already bought it. Too bad Ron doesn't really have any advice on how to improve water movement but only to select animals that don't live solely on a reefcrest.

Any of you physic majors feel like describing what Ron means by 1000mph water due to tidal action? I should re-read the article and post my question better but I don't have the time right now.

Troy F
11-23-2001, 05:20 PM
Shane, sounds like some great experiences. I'm going to get certified next year if possible. The only problems I can forsee are that I'm a terrible swimmer, terrified of the water and claustrophobic. My boss is a diver and has a great underwater camera. I should try to get his pictures for the next reef club meeting.

I just received the Wave2K promotional video, it looks pretty good. They claim it has been running problem free for more than 18 months. I'm really leary of the design but I'll tell you, it sure does do a good job of creating the motion we're all trying for. I think it costs about $448 cdn though so they'll have to satisfy a few points of concern before I fork that over.

Steve could you share your plans on the sinusoidially varying valve arrangement? I'm most interested in a parts list.

Silverfish
11-23-2001, 06:08 PM
Hey Troy, how ya doin'? I was looking at the wave2k and it looked like it was pretty big, (centre model) I was wondering what it would look like in my tank? 36"x18"x20" ... Probably be nice in a bigger tank eh?
I already have a lifereef overflow that is too big, wish my tank was drilled! images/smiles/icon_biggrin.gif
-Bruce

Acro
11-23-2001, 06:34 PM
hey troy quite watching video's and get that tank running images/smiles/icon_wink.gif I was wondering if the video is on a empty tank or stocked sounds like I'll have to come and watch it one day perhaps even help put some water in your tank hehe later jamie

DJ88
11-23-2001, 06:37 PM
mmmmmmm. reef shark...... images/smiles/icon_biggrin.gif Man that is an animal... oh to have a 10,000 gallon tank for a shark.. sigh..


Hey troy you coming by sunday? Scott aske dif it was ok.. COME ON OVER! only a three beer tax will be levied.. images/smiles/icon_wink.gif

StirCrazy
11-23-2001, 07:42 PM
Sure Troy I will post the equipment when i figure it out, the guy who did it did it from the top of his head and never made drawings or such so I am re inventing the wheel images/smiles/icon_smile.gif but it isn't that hard.. I will post what I am using and how much as I build it and I am also goign to do a detailed set of drawings for it.. (go figure that I would actualy be doing what the military trained me for on a fish tank images/smiles/icon_biggrin.gif

I just had knee sergery today so if I don't answer much this weekend it is because I am druged up on the couch watching my 50" tv images/smiles/icon_biggrin.gif images/smiles/icon_biggrin.gif

Steve

DJ88
11-23-2001, 07:54 PM
Get well there Steve.. images/smiles/icon_smile.gif

What kind of Knee surgery? Arthroscopic?

StirCrazy
11-23-2001, 08:54 PM
ya I think thats what it was called hehe the 3 tubs in the knee and they poerate on video through the tubes..

Steve

Troy F
11-24-2001, 11:35 AM
Jamie, you are welcome to watch the video anytime and it is on a stocked tank (quite nice actually).

Bruce, I think the Wave2k would look huge on a 36" tank, I believe it is 18"x18"x4".

Darren, I didn't know you were having people over but if I get time I'll definately swing by.

Steve, I'll look through my files, I believe I have some e-mails from Robert that may help. There is also a guy on reefs.org that was going to make a version that would have a sourceable parts list. I'm going to look into finding him again.

DJ88
11-24-2001, 01:10 PM
Troy,

Scott emailed me and said that you guys woudl be in the area and asked if it was ok for the two of you to come by..

Scott,

You making dates and not telling the others interested? images/smiles/icon_wink.gif

lol