Tank turnover rate

[keeperfish]

I have a 75 gal display with a 75 gal sump and a mag 18 pushing up about 8 feet from the basement with one 90 degree angle. I just filled a five gallon bucket in 36 seconds on the return hose from the display running back into the sump. If my math is correct that is cycling 60 gal. of water(displacement of rock) just over 8 times an hour.
So my question is this....on the overall turnover rate for the tank do I include what my powerheads are pushing or just what is running through the sump/fuge?:headshake2:

[Almondsaz]

I include the powerheads, the return pump if you are trying to determine how much movement overall. The value of what is running through the fuge I believe would be accomodated in the return pump calc. Hope that helps. And depending on what you keep in your tank (FOLR or Reef) you would need from 50x to 70x for turnover.

[Amphiprion]

That works. Feel free to experiment with high flow rates. I have over 150x.

[AnnetteG]

Okay, how do you figure out how much flow you have and if it's enough or what? I know you all always say you can't have too much, but I had so much that I was getting an unstoppable cloud of micro bubbles and the only way I got rid of them was to turn down the flow on my main pump a bunch. I did have a Tunze 6080, but I decided to go ahead and sell it because *every* time I had it running, ALL of my ricordeas and mushrooms would shrivel up to nothing. I tried moving them all over the tank, but there just wasn't a place that gave them the light I wanted them in and a flow level that didn't cause them to shrivel up like raisins. Now that I've got the flow adjusted to where I've gotten rid of the micro bubbles and I just have 2 Koralia 4s in there, my shrooms are all nice and fluffy again. I've got a few sps frags but I'm keeping them near the top where they're getting a good amount of flow from the koralias and the return pipes. But, if I go by these rules, I would think I have no where near enough flow. I do plan to add another K4 soon. If I could find a way to keep my pump running at a higher rate without producing a cloud of micro bubbles, I'd have more flow that way. It's an Iwaki md70.

Advice? Thanks!

[Catpicklesdog]

I calculate only using my powerheads. I don't include the return pump.

I've always read/heard/calculated that you need 10 x for FOWLR and 25x for reef.

Saying that though I currently 39x.

[Dale W.]

As cat mentioned, 10 to 25X is the common number in turnover rates depending on what you have in the tank and for a set up. 10x is bare minumum IMO. You cant really go by the specs on your pumps to determine the flow rate. They give you a good idea but that is about it.

Amphiprion,
You mention that you have over 150X turn over. How are you achieving this and in what size tank? If you have a 100g tank, you are pushing 15,000 gallons an hour. Not trying to be rude or anything but when I read that, the first picture in my head was a flushing toilet :D

Another thing that should be concidered besides turn over is surface agitation. Very important for O2 exchange.

[Almondsaz]

My reef with fish, softies and only a couple of SPS is ~37x turnover

If I was heavy into SPS the turnover rate should be higher which I believe is in the 50-70x turnover. I have always included the return into my calc so it may be slightly overstated. Without the return it is about 30x.

[salty420]

i've never counted my return pump. i've got a koralia 3 and 4 and a SEIO 1500 on my 75g so that puts me at 3550gph which is just above 47x turnover and i STILL have nasty buildup on my sandbed! but unlike you annette, none of my corals (including shrooms) mind the flow at all and i certainly don't have microbubbles, i wonder why you were getting those..?

[AnnetteG]

the only things I can think are how absolutely fast the water was moving through the sump with the Iwaki fully open, it was making a LOUD splashy waterfall after the water goes through the refugium. On that end of the sump, there are only 2 baffles, where I've noticed most people have 3. Unfortunately, I didn't figure that out when we had the whole thing taken apart and my husband was redoing all the baffles. So now, it's done and I've got to live with it, I guess. The only way to quiet and slow that waterfall is to put a piece of eggcrate with filter spongey stuff draped over it in the chamber directly after fuge. We had it like that when we were running the tank empty for the first couple of months, which is probably why I didn't realize how loud it would be and how many micro bubbles there were. We'd only done it that way at the time to clean the water because I'd put in live sand from someone else's tank and it was nasty and we didn't have a skimmer yet.

[Amphiprion]

How are you achieving this and in what size tank? If you have a 100g tank, you are pushing 15,000 gallons an hour..
I like to think of it as a washing machine ;). I use modded Tunze pumps (4 nanostreams, 1 6100 stream). While volume is high velocity is low and very diffuse. 75 gal, BTW, so ~10000 gph.

[Dale W.]

OK, volume vs pressure(velocity) makes a big differance. I am not sure how you modified the pumps but the 6100 pushes about 3100gph and the nanos, depending on which ones push about 100gph each(420) so with stock pumps in optimal condition you are at about 45ish times on the turn over.

This could start a new thread "volume vs pressure in relation to turn over rates"

[Reefscape]

This could start a new thread "volume vs pressure in relation to turn over rates"


That would be a great idea Dale....Would be an interesting discussion....

[Amphiprion]

OK, volume vs pressure(velocity) makes a big differance. I am not sure how you modified the pumps but the 6100 pushes about 3100gph and the nanos, depending on which ones push about 100gph each(420) so with stock pumps in optimal condition you are at about 45ish times on the turn over"
Not entirely accurate. Even the small nano is 660gph & modding ups it to ~1400. The modded 6100 is 4000+ gph.

[Dale W.]

Notice I said stock pumps and was refering to the 420 in (). For those the info is accurate as far as I know. Those are not the exact specs of course but close.

So I guess the question would be, how did you modify the pumps and what model are you refering to for the "nano" pump?

Not trying to slam you or anything so don't think that. I am just curious is all.
If there is a way to mod some of the pumps out there and still pull the same wattage, it could be benificial to others.

[keeperfish]

Well with my kor 2 power head I am pushing about 14x an hour. I initially had two kor 3 power heads in there and my clownfish had 0 non turbulent areas to go. That lasted for about 3 days and I removed both of them and repalced it with one kor 2. Flow versus pressure would be a great discussion I am sure it has alot to do with placement.

[Amphiprion]

Notice I said stock pumps and was refering to the 420 in (). For those the info is accurate as far as I know. Those are not the exact specs of course but close.

So I guess the question would be, how did you modify the pumps and what model are you refering to for the "nano" pump?

Not trying to slam you or anything so don't think that. I am just curious is all.
If there is a way to mod some of the pumps out there and still pull the same wattage, it could be benificial to others.

I apologize if I came across as being somewhat terse, etc., but I was replying via a PDA, so I was limited as far as message length. I didn't take offense at all. I am not sure what model of pump you are referring to. The Tunze nanostreams are only available in 6025 (660 gph), 6045 (1189 gph), and 6055 (264-1, 453 gph--controllable). I have the 6025s. It is difficult to describe the mod, so I'll link to it when I am actually on my own computer. The thread includes all the mods known and has pictures describing the process. It is incredibly simple and one of the best mods you can perform, IMO. BTW, the mod extends the 660 gph to 1400+ and only consumes ~7w! After replacing the seios I had with these, the temp. dropped by several degrees.

[Dale W.]

Nope, didn't take offense at all. Just wanted to make sure that you wouldn't as you can not tell how people are when you are not face to face.

[Amphiprion]

As promised, here is the nanostream mod thread (http://reefcentral.com/forums/showthread.php?s=&threadid=1025361&perpage=25&pagenumber=8).