Some Advice Needed

[fatfishman]

Hello Everyone

I have a few questions about marine tanks, and would be very grateful of your expert answers and opinions.

Firstly I now understand that that biological filtration is done in the the sump by live rock rubble and in the main tank by currents through the live rock in the tank, but what I dont understand is where and how is mechanical filtration carried out in a marine tank? because I have not heard very much about it

My second question is about the sump inlet and where is it drilled, is it on the water level so that water trickles in, or is it completely submerged below the water level? If using a sump is it necessary to have any more glass structures and such in the tank or can all of the rest be in the sump?

Thankyou for reading (and try to humour me and my lack of knowledge)

 

[n3ont3tra]

I can answer the first question: Many marine tanks don't have any mechanical filtration at all! If they do, it's usually in a power filter (HOB). A lot of tanks have no mechanical filtration because sponges and pads will trap detrius and cause nitrates. It's usually okay to have in a FO or FOWLR but it's better to avoid mechanical filtration in reefs.

 

[1entra]

I use a fine filter sponge above my LR rubble in my HOB refugium in my reef tank. It can/will only cause nitrates if you do not stay on top of the cleaning or changing filters regularly!

 

[chrissaysyes]

canister filter for me. Filled with a pad, rubble, and chemical media. Like everyone said, that pad needs lots of cleaning.

 

[SkiFletch]

Agree on the mechanical stuff. Also remember, the pores in LR can trap detritus and waste which is often removed by bristleworms and other detritovores naturally, or during water changes.

As for the sump questions: Where to drill the tank depends on where you live (US or UK). In the UK, you can drill anywhere (top, bottom, back, side) as tanks are all plain old glass. Most tanmks in the US have tempered glass bottoms, pretty much forcing you to drill the back or side. In any and all drilled cases, an internal box of glass or acrylic is a GREAT if not required idea to keep snails and other organisms out of the overflow. Clogged overflows = wet floor . For a little google research into overflows, lookup the following; Calfo Overflow (for drilling back/side), Durso Standpipe (for drilling bottom), and Stockman Standpipe (also for bottom).

 

[fatfishman]

Ok Thanks Alot Guys

SkiFletch the thing that i dont under stand is if the tank is drilled in the bottom or low, than if the return pump breaks down wont your entire tank empty into the sump and then onto the floor, whereas if it is at the water level it will only empty a little bit enough for the sump to contain?

Am i right or (much more likely) am i missing something?

 

[SkiFletch]

It's the standpipe built that is your first line of defense. You have 2 (or 3) levels of protection depending on the style of overflow you choose. The standpipe versions (durso and stockman) are hard-connected (glued or threaded) on to the bulkhead and only open at the top of it. In these situations, the first wall of continuous siphon protection is the internal weir box. Once water gets to the bottom of the teeth of the weir, it doesn't overflow into it, and can't cascade down into the sump. If that leaks, water will only cascade into the sump up to the top of the standpipe which is your second line of defense. If the un-thinkable happens and your bulkhead fitting AND internal weir catastrophically fail though, you will have an empty tank with a Durso or Stockmann type.

If you use a calfo style overflow (hole drilled in the back slightly below the water line), if all both weir AND bulkhead fail, you get a lot of water on the floor, but not an entirely empty tank.

Durso and stockman standpipes take up less room behind the tank, thus enabling you to put it closer against a wall, while calfo systems have their "business end" sticking out the back of the tank and require prolly at least 6" clearance for most medium to larger tanks. Look up the overflows and you'll have a better understanding

 

[fatfishman]

Ok Thankyou SkiFletch This is Very Helpful.

I appreciate it and cant wait to set up my own marine tank i am thinking of buying a second Hand 5.5ftx2ftx2ft with a sump, not definate but this is roughly the size tank that i want. What size tank do you have ?

If anyone else has anything else to say please feel free, this discussion is still open.

 

[SkiFletch]

Heh, I've got a 3x2x2' so yours would be almoast double the size of mine

My tank runs with 2x1.5" calfo overflows with one single weir. One overflow is drilled slightly higher than the other both to help keep noise down (oversized drains do work better in that department) and in case one clogs, I've got a second to take over. Either overflow is capable of handling the entire flowrate.