Refugium Flow overflow vs return water

[goblin072]

I'm getting ready to add a 25 gallon refugium to my 300 gallon FO.

I was going to T off my overflow return but I had read that using return water will gunk up the refugium with detritus and that using a T on the return would keep this from happening.

I plan on using Miracle mud and Chaeto algae. I'm thinking around 300 gph through the ref.

Any thoughts on which is best for input? Overflow vs return water.

Thanks!

[V]

Personally ether works for me. It depends on your methodolgy. Ok, so that word doesn't look right, d@mn 5th grade engrish, why did i skip it lol

Animals that grow in the fuge do like the scraps that come down the chimey, but if yor one that wants to trap it before it reaches, best dump in the sump first.

[PhotoJohn]

300gph is way to fast for a fuge IMO most ppl think 10x turn over is max for a fuge. after you have mud/sand/rock and macro in there the turn over would be really fast. the point of the fuge is usually a place for macros and pods...slower turnover will help the macros "scrub" the water better

[saltaddict]

I plumb off the main drain to the fuge with a flow valve to decrease the rate of water dump into the fuge. The food particles feed the lifeforms in the fuge. You will end up countless baby stars and pods and they must eat too.. Just my opinion.

[goblin072]

The main purpose of my fuge is to decrease nitrate levels and maybe add some nutrients to the tank. I don't have live coral or live rock. There is something in those systems that Tangs need. No one seems to know what it is. Probably some trace element that is needed in a reef and not in a FO system.

I'm not sure if I need PODs, I don't have anything that would eat them.

My current return is 1.5 inch. I was thinking of using 1 inch to the fuge. The pipe and ball valves are less expensive for 1 inch.
Or should I just go 1.5 inch to the fuge?

I think the person that did not like overflow water in his fuge said that they eventually become counter productive. Too much gunk gets in them. So he switched to using return/skimmed water. For me it would be easier to use overflow as its free gravity feed.

If I go return water I'll need to upgrade my pump, I don't want to loose 200-300gph in the display to feed the fuge.

I was wondering how do you people figure out just what 200 gph is? Do you put a 1 gallon bucket under the output and time it?

Short of an expensive flow meter I wonder how most people are figuring out the actual flow.

Speaking of flow,

1. My overflow has 32 teeth (maybe 24" of teeth) that are like 1/4 and maybe 1.5 inches tall. Not sure what it can handle I'm guessing maybe 1500-1800 gph. The 1.5 inch drain has a siphon effect and can have 42 inches of water above it for a pressure return.
- I was only pushing 400gph through it. I since upped it to 750gph.

2. The other flow source is a closed loop that does 650 gph into canister and UV and chiller.

Is this enough flow in a FO?

All my input pipes are 1 inch. Not sure what the limit is for a 1 inch pipe in terms of pumping. I have heard that 5 ft/sec flow is good but don't go higher. I would need about 9ft/sec flow to get 1500gph through it. They don't really say what is bad about going to 9ft/sec other than you loose more gph from friction. I think that makes a bigger difference in a 100 foot run not so much in a 6 foot run of 1 inch.

Any thoughts on improving the flow?

Thanks..

[CarmieJo]

I run my overflow into my fuge. It is easy to determine flow if you have a pump but if your whole fuge is gravity fed I am not really sure how to do so. I guess you could use a bucket but I think you would want a big bucket if you are looking at 200 - 300 GPH.

[V]

You wouldn’t have guessed it, timed out due to working, then lost my post.

Summery, is your focus is on nitrate reduction, then set your bed for the future, throw in some rockwork in a circle, & if your interested in macro, then do it in the middle. KISS method bud.

The guys are correct, fuge by nature are slower, or else it would be called a sump!


So …….im assuming no sump? You haven’t mentioned one.

Id aim for larger diameters if you can afford them, especially when you factor in backpressure due to you messing with the return flow. Not to mention 1.5” is a nice starting diameter for any modifications in the future

Ok, so forgetting your closed loop, cause that’s just a bonus to me on the turn over front.

Im just going to give a simple example, as follows…. a sump, RT pump in the sump, DT above it, then a Wye on the dump pipe for the returns.

Your asking for real world, this is a real word example - & I’ll even use your values bud.

Most of the time, when working out flow, or in this case, proportional direction of flow, you just use rough values of 25%, 50%, 75% ect You can work out what’s what on your restrictor or directional taps you include in your plumbing pretty easy.

So let break this puppy down….


Tank:300g
RT pump: 760g/per hr

760/300 = 2.53 TTO/per hr

Now working a 50/50 split at the Wye, then that’s

760*2.53 =1922.8 / 2 = 961.4 each side. (50/50%)

With me so far….?

Now lets say you want 75% on the right, & 25% on the other.

760*2.53 = 1922.8
1922.8 * .75 =1442.1
1922.8 * .25 = 480.7

So that’s …
1442.1g/per hr on the right
480.7g/per hr on the left

Easy yeah?

[saltaddict]

Ok V - too technical for me. My way - hook it up, adjust the ball valve and watch how the water is swirling in the fuge. If you think it is too much- close the valve a little, not enough - open a little.

[V]

yeah, good on ya salty redneck...lol

[saltaddict]

That is the woman's way!! If it doesn't work - change it!! LOL

[goblin072]

Sorry forgot to mention that I do have a sump. The refugium would be a add on.
Right now I have a little giant 4 pressure pump doing about 800gph on the return. The overflow goes to a 50 gallon sump. The 1.5 inch empties to a drip plate above a bunch of bio balls then to a sponge filter then to a small compartment that has the return pump. (not enough room for internal skimmer) the skimmer is external and plumbed to the sump. The skimmer is running off a mag 9.5.

The closed loop is just for UV, chiller and polishing filter (can run carbon in it as needed) it does maybe 600gph.
I'm getting rid of my chiller to make some room for the refuge. I'll connect a 1.5 inch PVC from the fuge to the sump. Almost exactly like this fellow did.
DIY Refugium
It won't be huge but should put a small dent in the nitrates. I run a Phosphate reactor with Rowa too.
I checked the nitrates with a test strip. They read 40. My tank maintanace person always writes 0 nitrates in the log book. I was thinking it was impossible for them to be zero as I have some hair algae that is living off something. I'm thinking he has a bad test kit. Even doing 30 gallon per week is not enough to zero out nitrates. I'm not sure how much a 25 gallon refuge with DSB and algae will lower nitrates. Hopefully it lowers them to 10 or so. If it fails I can always get a nitrate reactor. They are pricey though.

Not sure why you multiplied my overflow turn over rate by 2.53.
My current total flow is 750 with overflow + 600 gph closed loop = 1350 gph. 1350/300 = 4.5x Total tank turnover per hour.

Are you saying to shoot for 1922.8 gph which would be a 6.4x turn over rate?

I could swap out the overflow return for a Iwaki Md70rlt, that would give around 1300-1400 gph at 8 feet head. That would pretty much max out my overflow.

Going from a 4.5 to a 6.5x turn over what is the benefit? I've read its good but they never really explain why its good for a FO to have a high turnover. I'm not getting any Nitrite or ammoinia spikes.

[V]

i left out the closed loop on purpose, to me- its just an added extra bonus on water movement, im assuming its in the DT?

was working out your actual gears regarding the transfer with sump & DT as an example bud.

High turn over is good for a number of reasons. Ive got fish only systems as well, & imo you can never have too much. admittedly some of my outputs could drill a hole straight through the earth, but then again i dont have anything that could be classified as toy fish ether

Waste & detritus removal, proper circulation, oxygenation & efficent gas exchanges, there's heap of reasons, not to mention fish prefer some flow to interact with.

Even from standard marine turn overs, your still low in the range bud. Your best to max out everything you can, or that your system can handle. add-ons are easy, & fuges being one of the most easiest & interesting.

[goblin072]

Thanks,

I could up the return pump to 1300gph

The closed loop does help tank circulation. 1.5 inch drain poping out of the sand eventually outputs to a adjustable spray pipe sticking out of the sand on the opposite side of the tank. So its sucking in 600gph on one end and pushing it straight up on the other side (The tank is a 360 walk around)

I could up the closed loop to maybe 1000 gph. Thats alot of water coming out of one 1 inch pipe at the bottom.

So 2300 gph is probably max.

After that would have to put in hang in the tank pumps which would detract from the looks.

[V]

i got around to checking out your link.

he pumped into the fuge from the sump. But yeah, i see what your idea of connecting them. yup- pretty straight forward bud. the world is full of possibilities when it comes to tanks.

You can offset the tanks higher, that way gravity aids in movement, you could drop the size of the interconect plumbing & go 2 smaller ones (redundancy) . you can pump from the sump into the fuge exclusive via a power head, tap off your return line & feed the fuge that connects to the sump, or tap off DT dump line into the fuge, then the sump, you could attach it cascade style into the sump instead of interconnect. there are heaps of different routes to go, each one has merit, each one personal.

question for you, if you have a 360deg tank, how come you havn't gone 360ish deg sump in the same design underneath?

[goblin072]

Thanks for the insights.

I'm not sure what a 360 sump is. I did not build it, I'm just modifying what I have to work with.

I can access the sump from both sides if that's what you mean.

I don't have room for a circle of rocks. I could put a small rock in the fuge. I could remove a 1 foot thick layer of bio balls and replace it will live rock. Would probably reduce the ability of the wet/dry in reducing Ammonia - Nitrite - Nitrate.

If I get to crazy I'm worried that I would be replacing high nitrates with High NITRITES or Ammonia. So probably should keep some bio balls.

[V]

regardless if its bio balls, rockwork, or your latest "nerd of the year" award, if its in the same trickle situation/setting, the same bacteria populate. if its only running fish, then focus (as your doing) on a way to convert your nitrates for the future with a decent water change program till its ready & functioning