Sump Advice

[londongreg]

Hi All,

I posted on this forum a few times about a year ago when my flatmate and I first set up our 180litre marine tank. The advice was invaluable then, although I've since lost my login details, so have signed up again!

Anyway, we're thinking about installing a sump. The problem though is that the tank stand is partitioned with a load bearing plank of wood in the middle, which leaves two small cubby holes either side and not much room for a sump. So, we're faced with a few difficulties.

However, as the back of the tank is open, I've thought about extending the sump out behind the tank stand, building it high, and even perhaps partitioning it, so that the in and out pipes are on the same side of the sump, with the water flowing away on one side, around a middle partition and then back towards the return pump. Is this possible/doable? Would water flow properly like this? Or is a basically square sump acceptable?

I've got about 35cm x 45cm to play with, and I'm thinking that at 30cm high (I'd build it around 45cm high to allow for power cuts etc) this would give me about 45litres of water capacity.

Now, add to this the fact that I know very little about sumps and am in dire need of some advice on design and what to stock in it, and you can see my problem! Everyone seems to have different ideas about DSBs, refugia, plastic bioballs etc etc, so some advice is very much needed!

Any comments or pointers to relevant resources would be most welcome.

Cheers!



Since then it's been a rollercoaster of a learning experience, but we're slowly getting there.

 

[Adrinal]

First lets nail down some things.

Sump by definition is the lowest chamber of water where everything will flow to when the power is off.

I like to have the sump for nothing but water and heater and a place to mix in additives and what not. Anything else will take up space, volume that is. But, in reality we have limited space and the sump also becomes a refuge, or filter, or sick tank, or evil critter box.


If you are going to use the sump as a true sump, the partition can help to get the bubbles out before going back up to the display. If your going to use it as any kind of filter, refuge or whatever you will have ... free flow... ya use it, man!

Here is the catch. Don't make anything so tight, so hidden, so have to bend over to work-on.... that you don't. Out of sight, out of mind; so don't keep it out of sight and reach if if shouldn't be out of mind.


I personally like no light live rock fuges the best. JIME

 

[SkiFletch]

Ah you have one of "those" stands. IMO, your best two options are to see if you can shoehorn in a pair of 10g tanks in there, drill two bulkhead holes in either of them, and drill a passthrough hole through that middle wall in the stand to connect them together. Or you could connect them behind the sump with bulkhead fittings if you like. Option 2 would be to use a remote sump... There's no rule other than convenience that says the sump needs to be under the stand. Ge creative, put it under a desk next to the tank, in another room, or somethin. You've got options other than just under the stand

 

[londongreg]

Ah you have one of "those" stands. IMO, your best two options are to see if you can shoehorn in a pair of 10g tanks in there, drill two bulkhead holes in either of them, and drill a passthrough hole through that middle wall in the stand to connect them together. Or you could connect them behind the sump with bulkhead fittings if you like. Option 2 would be to use a remote sump... There's no rule other than convenience that says the sump needs to be under the stand. Ge creative, put it under a desk next to the tank, in another room, or somethin. You've got options other than just under the stand

Ah Ski Fletch, you are the wisest of fishmen. Interesting - I hadn't actually thought of that option to be honest. I'm sort of stuck for space in the room, so there isn't really room for a desk or somewhere else to hide the tank, and I rent, so the landlord probably wouldn't be too happy about me drilling holes in his wall!

So that leaves option 1. But how wide should a hole like that be? Where roughly in the tanks? (ie top, bottom etc - I'm presuming in the middle though), and is there a danger of dead spots in both tanks at all?

Actually, since I've posted, I've found an example of someone who took out the middle partition by bracing it temporarily, installing the sump and then putting in new bracing around it. I was thinking this would be a good idea as it would give me a far bigger sump, although it seems tricky, not to mention dangerous if things to wrong! your way seems a lot more sensible!

 

[SkiFletch]

Well, were it my tank, I'd prolly do the option you discovered cause you're right it makes thing's a lot easier. If you do decide to go with the 2-tank route, you'd be best off drilling the tanks near the middle.

 

[londongreg]

OK, so I've decided to go with Ski Fletch's twin tank idea and I've ordered the pipe work (32mm), overflow box and bulkheads (40mm) to join the two tanks.

I've just got to find the right powered return pump (so I need to calculate the power needed), and plan the configuration of the two tanks.

Any ideas on either?

I'm thinking about having the refugium/DSB take up most of the second tank, with a small section at the end for the return pump. This will leave me most of the first tank (after the water in compartment) for putting stuff in - heater, possibly my (Deltec 600) skimmer as well.

Anyone got any tips on this?

I was also thinking that because of the 40mm bulkhead between the two tanks, it might be a good place to fit some sort of rowaphos or activated carbon filter too.

 

[SkiFletch]

I wouldn't put anything between the tanks (carbon/rowaphos), cause if it gets clogged... not good

As for flowrate, 180L display capacity should have around 5 times that through the sump, so 900LPH. Look for a pump rated around 1200LPH to achieve this and prolly 25mm bulkheads for the drain...

 

[chrissaysyes]

are you drilling these yourself? If so itd be cool if you'd document and maybe illustrate a bit here. I would learn a lot from that.

 

[londongreg]

I'm going to have the tanks made at my lfs, pre-drilled I think.

I will take a few pics though to document!

Ski Fletch - I've got 32mm bulkhead on the drain, well the bottom of the overflow box, if that's what you mean. Will that affect my flow rate? Do you still think I should be looking for a pump with 1200 lph power?

The pipework has arrived now, and I've hit a snag! The 40mm bulkheads are way too long, so if I carry on with my plan, I'm going to have to cut them down, or I'll have hardly any room for the refugium. I'll try to post the diagram that I've sent to my lfs for a quote. They reckon I might not have enough water volume to make the whole project worthwhile.

Meanwhile I've got serious nitrate issues (50+) so something's got to happen soon!

What do you folks think?

 

[SkiFletch]

well a few thoughts here.

The bulkheads are technically designed to be oriented in the opposite direction. Although they can work in the manner you propose usually the "short" side is inside the tank. Also, if your drain is 32mm, the double tank-connecting bulkheads don't need to be 40mm, they can be at MOST 32, and even 25 would likely work.

As for a return pump, a 32mm bulkhead can drain a bunch of water, so if you wanted, you could increase your return pump to something more like 1600lph, but if you already have the 1200lph pump you can use that. What you need to avoid is having a pump more-powerful than the drain. Having a drain more-powerful than the pump is no big deal as the drain auto-corrects with air.

And lastly, installing a DSB in a sump is not a good idea. If you really want a DSB, run one remotely off your sump using a 5g bucket. That way when it's time to clean and install a new DSB, you just toss the sand in the bucket, add more, and go nuts.

If nitrates of 50ppm are your problem, in the short-term do a 50% waterchange, and then consider running a nitrate reactor in your sump. Will take a while to establish but should clear things up for you