Sump Larger than tank = Bad?

[nuggetsgotmilk]

I am about to start setting up a 30 gallon rimless tank. I have a very nice sump for about a 150 gallon tank. Not having space under the tank is not an issue but would it hurt the tank having the sump be larger than the tank? I would most likely fill the sump with live rock ect. Has anybody tried this? Thanks, Ben

 

[bcavalli]

+1 Brandon. Ive always heard the bigger the better. Lol

 

[nickg]

Yep, and the more total volume the better.... I saw a 60 or 90 cube with a 200 gallon sump and fuge....

 

[nickg]

LOL, that's what she said...

 

[nuggetsgotmilk]

Alright thanks everybody! Now what about a larger Skimmer? I have a skimmer for a 150 gallon tank. Same thing bigger is better?

 

[nickg]

With the skimmer... Brand is important... Get a GOOD one the first time... And get one big enough for the next build...

 

[acroholic]

I bought some live rock from a Member back in 2008 that had a 70 gallon RR corner tank, and a 300 gallon sump.

There is nothing wrong about it, and it would help the stability of the system, but personally I have always regarded them as a bit wasteful. You have to do water changes and treatments and use additives to whatever volume you are dealing with, and personally I prefer an appropriately sized sump and to have the largest percentage of the system water volume in the Display Tank.

I would not want to have to spend money for salt to do water changes and supplement KH/Mag/GAC/GFO or whatever else to a large volume of water no one ever sees. I guess I don't see it as an issue with a large volume Display, if you see whatever logic I am trying to apply, if there is any, hehehe!

 

[bcavalli]

nickg;964655 wrote: LOL, that's what she said...

Exactly!

 

[rdnelson]

Bgcoop8784;964663 wrote: Not trying to go against anything you said by any means, more of a question. If there isn't anything in the sump that is expending the KH/Mag/GAC/GFO, would it really take any more of it? I understand having to use more salt, but once you have it in there it's there unless you have corals or algae in the sump consuming it, right?

Following your lead, I would expect that the amount of water change required in a heavily loaded system would be more than a system that was not heavenly loaded. A fixed amount of nitrate production spread out over a larger volume of water.


I know you all think I have no heart but now I have an ultrasound to prove it.

 

[nickg]

All of our beautiful tanks are "heavenly" loaded Rich... Dang autocorrect...


"I would expect that the amount of water change required in a heavily loaded system would be more than a system that was not <span style="color: red">heavenly</span> loaded."

 

[tonymission]

For example, 10% water changes are based on the total volume so a 300g sump with a 30g DT would mean 33g water changes instead of 3. I think that's his point, and it's valid.

 

[rdnelson]

Bgcoop8784;964677 wrote: Yeah, but 10% is just a guideline. If you have 300 gallons of water with one clown fish, a bi-weekly 10% waterchange would be way overkill. Waterchanges in my opinion should be done according to the bioload and the system set-up, some tanks require more frequent waterchanges than others.

Exactly. Say the fish and corals create 10 units of waste and consume 10 units of calcium, etc. Diluting those 10 units of waste in 300 gallons of water has a much lower effect than it would in 30 gallons. Consuming 10 units of calcium out of 300 gallons would lower calcium content much less than in 30 gallons.

And yes Nick, that is heavenly. LOL.


I know you all think I have no heart but now I have an ultrasound to prove it.

 

[nuggetsgotmilk]

Gotchya! Thanks guys!

 

[hiimsean]

Also you have a sump "rated" for a 150g tank. How many gallons does it actually hold? That will influence how to size your skimmer. Most likely it's 30-40g sump so you total system volume will be roughly 60g. With the skimmer it's better to get an appropriate sized one or at lease closer, I'd say something rated to 100g or less like a Vertex Omega 150, Aquamaxx CO1 or SRO100 or similar. Like others said, get one with a quality pump.

 

[nuggetsgotmilk]

The skimmer I have is the Reef Octopus Classic 150- Internal. It has a great pump on it and was used on a friend of mines tank. He ran this equipment on a 90 gallon reef.

Tank- 30 Gallon Deep Blue Rimless Shallow

Skimmer- Reef Octopus Classic 150- Internal

Sump- Eshopps RS- 300

 

[nuggetsgotmilk]

Just checked it out and the sump is for a 225-300 gallon tank! That seems a bit large for a 30 gallon setup!

 

[seth the wine guy]

Bgcoop8784;964663 wrote: Not trying to go against anything you said by any means, more of a question. If there isn't anything in the sump that is expending the KH/Mag/GAC/GFO, would it really take any more of it? I understand having to use more salt, but once you have it in there it's there unless you have corals or algae in the sump consuming it, right?

+1 About to say much the same thing but scrolled down and saw you beat me to it.

tonymission;964673 wrote: For example, 10% water changes are based on the total volume so a 300g sump with a 30g DT would mean 33g water changes instead of 3. I think that's his point, and it's valid.

Throw rules like 10% WC out the window along with so many lbs of LR per gallon or watts of lighting per gallon. That's Petco starter advice. Larger the total water volume to DT volume the slower the depletion rate of nutrients/elements by the creatures it's intended for. So, the slower the replenishment rate needed.

To exaggerate the point. If you had a swimming pool size sump for a 40g tank, you could probably never do a water change for as long as you owned it. (Especially given most reefers don't last more than a few years!) Depletion rates would happen so slowly there would never be any parameter swings and things would slowly adapt to the minuscule drops in elements or rise in NO3/PO4.

GET THE BIGGEST SUMP AND BEST SKIMMER YOU CAN AFFORD. TWV is one of the keys to a stable tank.

 

[tonymission]

So I would just factor my dosing based on cal fluctuations from day to day assuming that is consumption by my sticks?

 

[acroholic]

Well, you should always have at least a properly sized skimmer and sump volume, but I would rather have the majority of my system volume in the display where I can keep more fish and corals. Personal preference, I guess. Just seems a waste to have a ton of water and the expense of heating and cooling it, and whatever else is involved with maintaining it, if you don't get to use it to display and grow corals and fish.

 

[seth the wine guy]

tonymission;964777 wrote: So I would just factor my dosing based on cal fluctuations from day to day assuming that is consumption by my sticks?

Yes. But, we have to do that anyway and it can be a moving target. More stable the tank is the less that target moves. Many things factor into it as well.

Example from my tank-

I can have my Ca reactor dialed in perfectly and maintain near constant KH/Mg/Ca levels for months on end. I change my MH bulbs every 4-6 months. The explosion of growth that happens right after bulb change sends my tank into a KH downward spiral and I have to dose and adjust my Ca reactor PH level to compensate.

Same goes for PO4 levels. I'm happy with them anywhere below .10 and ideally have them .02-.05. But, if for some reason I let them creep up over where I like to keep them and drop the levels quickly, there is a growth explosion that plummets the KH. I have a 120g DT and 120g sump. I can't imagine how bad it would be if my sump were smaller. I can go from 9.5dKH to 7.5 in just a couple days. I'd love the stability of say, a 500g sump would bring.