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Need help with picking out filtration set up for 75 g tank, not sure what to use.

Joined
Dec 21, 2010
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I'm trying to figure out what type of filtration would be ideal to use for my upcoming octo tank. I plan to have some live rock, but not a whole lot, as obtaining 40 lbs is not cheap or easy in my area. So having an extra means of filtration is expected and probably required for an OCTO since they have a lot of waste?
So now my question, what would be a good method or 2 to pick between for filtration?
I was thinking plumbing something like a Fluval 405 into bulkheads drilled into the back of the tank? And having a simple sump tank under the stand mostly just to house the protein skimmer, and add water volume. Or should I looking into making a full on wet/dry refugium sump filtration? Bascially I don't want any over the top type devices. For this I was kind of looking at the Proflex Aqueon Refugium model 2. Or the Crystal Sump - Sump 30
 
As far as live rock goes normally that is the best method of filtration... I have heard pluses and minuses about both wet dry or refugiums. Setting up a refugium is pretty easy, a shop light, some macro algea and a bit of live rock rubble and youre in business... you shouldnt need the canister filter if your sump is set up right with a good high rated skimmer and refugium. IMO the best way to set up a sump is to have it split into 3 areas... skimmer-return-refugium. with at 75% 25% split with the water flowing into both skimmer side and refugium side.

I would look into getting live rock on craigslist. If you are near any major city you should be able to pick it up any where from 2-5$ a pound which is much cheaper than getting it from the store. You can also make it yourself which is a good way to help save the reefs. Go to youtube and type in making your own live rock. You should find many helpful videos.

Good luck and :welcome: to TONMO!
 
Thanks for the insite so far. So what about the bulkhead/tubing sizes for the inlet and outlet to the sump, what's the proper way to figure that out? Have not come across any info yet for this on the net.

Also is that your octo in your avatar pic?
 
Yes that was my octopus Isis. She passed away the day after Christmas... She was something else thats for sure. That picture right there is a solid reason to have a secure lid for your octopus tank. She got out of her tank when I left the tank durring feeding one day, after that she was never quite the same and passed about a month later.

As far as how to figure out rate and speed of pumps. You start with figuring out what size pump you need for your tank. It is recommind to have 10x the size of your tank. So if you have a 55 gallon tank you would multiply 55x10 and come to 550. So after that you would find a pump that has a 550 or more GPH (gallons per hour) rating the bulk heads and tubing size are based on two things. The Tubing size is based on the pump you have. Whatever pump you get will have an outlet hole for you to connect hose to it, that size will determine which size you will need. Bulk heads are pretty easy, you will normally need a a 1 or 1.5 inch bulkhead for holes. A 1 inch standard bulk head has at best a 600 gallon per hour flow rate though most people normally only have about 300 gallons per hour movement though a 1 inch bulk head. So a 1.5 inch bulkhead is recommind if you only have 1 overflow.

Many people have different ideas as to what is best in regards to setting up tanks and plumbing. If you have a local reef club thats pretty active you might try joining that way you could have some local help if you ever need it. I am by no means an expert when it comes to setting up plumbing so research research research is important.
 
With as much water as you will be moving, I STRONGLY recommend two overflow bulkheads, each capable of handling the flow of the pump. It does not take much to slow down a return line (though they typically don't get fully blocked). My 65 has only one return and I have had issues with air in the line and quickly rising water. If the power goes out, I will almost always lose water to the floor when the pump starts back up until the air bubble clears (part of this is an oddity with the tank design but if we had used two bulkheads it would not be a problem). We even put two returns in Monty's 45 :biggrin2:
 
dwhatley;169382 said:
With as much water as you will be moving, I STRONGLY recommend two overflow bulkheads, each capable of handling the flow of the pump. It does not take much to slow down a return line (though they typically don't get fully blocked). My 65 has only one return and I have had issues with air in the line and quickly rising water. If the power goes out, I will almost always lose water to the floor when the pump starts back up until the air bubble clears (part of this is an oddity with the tank design but if we had used two bulkheads it would not be a problem). We even put two returns in Monty's 45 :biggrin2:

So are you saying I want two sump pumps in case one gets clogged? Otherwise I'm not understanding. Also why would you loose water to the floor? Is your sump inlet pipe not positioned in a way that the sump volume can take up the extra man tank water until you reach the pipe or bulkhead position on the tank?

I'd love to see pics of your set ups for sump bulkhead locations.
 
No, the other way around. You want two lines to the SUMP and one from the pump to the main tank. The reason I get water on the floor is somewhat complex due to the odd nature of this tank but essentially, the bulkhead that returns the water to the sump gets an air bubble, slowing down the water flow back to the sump so water is being pumped into the tank faster than it can flow out. If we had had two bulkheads for the water flowing to the sump, the slow down would not cause the water to rise in the tank. As a matter of detail, in this case, the water rises into an area that has been cut away (by the manufacturer) gets between the glass and the frame but even without the oddities of this tank, a similar problem in any tank may let the water rise to an overflow condition. Something as simple as a snail in the drain line can cause an overflow so having two reduces the chances to almost 0.

The tank talk (this) forum has photos of most of our build outs as well as some nice shots of other members' setups.
 
dwhatley;169459 said:
No, the other way around. You want two lines to the SUMP and one from the pump to the main tank. The reason I get water on the floor is somewhat complex due to the odd nature of this tank but essentially, the bulkhead that returns the water to the sump gets an air bubble, slowing down the water flow back to the sump so water is being pumped into the tank faster than it can flow out. If we had had two bulkheads for the water flowing to the sump, the slow down would not cause the water to rise in the tank. As a matter of detail, in this case, the water rises into an area that has been cut away (by the manufacturer) gets between the glass and the frame but even without the oddities of this tank, a similar problem in any tank may let the water rise to an overflow condition. Something as simple as a snail in the drain line can cause an overflow so having two reduces the chances to almost 0.

The tank talk (this) forum has photos of most of our build outs as well as some nice shots of other members' setups.

Ok, so two inlets and a single return for in case a 75 g tank, about 750 gph flow.
I"d "like" to do two 1" bulk heads for inlets (just due to space and size) and single 1" return, but that won't be enough return flow? I guess if I have to a 1.5" return could work.


Also I'm having trouble finding the tank set up thread, or at least the pictures. I went through about 20 pages and the stickies only found 2 tank set ups.
 
Another reason we like a 1.5" return is the way the water returns to the sump causes more O2 to get into the water... O2 is VERY important. I remember one time when Isis was acting very odd... not like herself at all. Well this went on for a little while and I went to search for a cause. The water was fine but when I checked the equipment it turned out the airstone that I had in the water was out because of evaporation. The second I put it back in the water she was acting like her old self again.
 
sk252006;169465 said:
Another reason we like a 1.5" return is the way the water returns to the sump causes more O2 to get into the water... O2 is VERY important. I remember one time when Isis was acting very odd... not like herself at all. Well this went on for a little while and I went to search for a cause. The water was fine but when I checked the equipment it turned out the airstone that I had in the water was out because of evaporation. The second I put it back in the water she was acting like her old self again.

I read that thread of yours actually a few weeks ago. And I'm sorry for your loss of Isis, such an amazing creature, just love the avatar pic, which is why I had to ask if that was your octo. I do have another question for you if that is ok.
Ok so if I were to do two 1" sump inlets, and a single 1.5" return, (or if I did 1.5" for all 3) what controls the inlet and outlet flow. I mean it does not seem like a "perfect" match for incoming and returning water, is the use of a valve on each ok to balance this out?
 
Thank you, I do miss her. She was a cool little octopus. That picture was a SHOCK! LOL That was not the first time she had done that. She was VERY interested in me and wanted to get a closer look I guess lol. That time I was just prepared for the stroll. Though I will say I was surprised I got the picture. I was so nervious that she would fall I didnt even look in the camera to take it, I was watching her to make sure she was ok.

The flow balances out based on the flow of the pump... if your pump is to fast then there wont be enough contact time for the skimmer, so yes a valve can control can slow it down.
 
Here are a couple of build out threads that I could immediately think of :wink:
DWhatley's Monty's Scavenger Tank
Lmecher's Upgrading to a 120 gallon
DWhatley's Octo Tank - Going Larger This is the tank that is problematic because it only has one bulkhead to the sump.
BlueSpotOcto's 75 Gallon Bimac Tank
Corpusse's 90 gallon custom cuttlefish finally almost done
DWhatley's Dual Tubed Tank
Paradox's 150 Gallon Cuttle Farm Army tank build!"

Joe-Ceph's Escape Proof (and idiot proof) Top / Tank Lid.
more top discussions with pictures
 
I keep a bimac, and I thought that tropical live rock would look wrong in a "West Coast" biotope tank. I decided to use local rock (non-porous so useless for filtration) and a wet dry trickle filter with bio-balls. The other reason I liked a wet/dry was because it was almost free, and live rock can be expensive, and also because LR takes up space, and I wanted a lot of room in my small tank (60 gallon) for my octo to move around. The downsides I found were that a wet/dry filter must have a pre-filter to take particles out of the water so that they don't get lodged in the bio-balls and rot (causing high nitrates down the road). I need to replace the floss filter every couple of days (hassle) and the biggest problem is that I the floss filter removes the food I put in my tank for filter feeders. I need to turn off my return pump for an hour after I put food in the tank, to give the filter feeders a chance to eat, but probably 15% of the food is left after that hour, and ends up in the filter floss, instead of being eventually eaten as it would be if I just had live rock and no floss filter.
The other advantage of live rock is that it supports a population of anaerobic bacteria, unlike bio-balls, which will reduce nitrate levels. That's why, if you use a wet/dry instead of live rock, you should also rig a Remote Deep Sand Bed (easy with a 5 gallon bucket and a bag of play sand) to house the anaerobic bacteria and reduce nitrates.

Also, when you read about needing "ten times the volume of your tank per hour" in flow, I think that is a recommendation for a reef aquarium, and that it is referring to flow in the aquarium, not necessarily through your sump. If you have any sources of flow other than your return pump, like korallias or a closed loop, then you can get 10x flow without needing to move that much water though your sump. Also, you might not need that much flow for an octopus tank anyway (although live rock needs a lot of flow to do its job well). I suggest you study the question of flow through your sump, as opposed to flow in the tank, before you design your overflows and plumbing. for example, it is not recommended to have more than 3-4 times the tank volume per hour go through a wet/dry trickle filter, but you still might want more flow than that in your tank.
 
It seems like most people want to keep Octopus tanks like how reef / saltwater tanks were kept 20 years ago. I'm not singling you out, but this seems rather typical. While Octos may not require the water parameters of a reef they are at least modestly sensitive to water quality.

For a 75 gallon you should be looking at least 75 lbs of live rock, maybe less if its really porous. If you don't want to put it all in the tank you can put some in the sump. This combined with a good quality protein skimmer and a refugium with any simple macro algae growing in it should work out very well.

As long as your drain hole is 2.5 with a 1.5" bulkhead (remember the hole size you need is bigger then the bulkhead size) then it should be fine. 2 is safer, but one will do. Your returns can be any size as long as they are big enough to account for the flow from your return pump.

Ideally you want your return pump to be about the same gph as your skimmer that way the drain is feeding the right amount of water to your protein skimmer. You can go over this but as mentioned additional flow, in fact most of your flow will be done with either powerheads or a closed loop.
 
I didn't choose a wet/dry trickle filter (bio-balls) out of a sense of nostalgia, or because I keep an octopus, but rather because I wanted my tank to look like a slice of the Southern California underwater environment, and live rock would have looked like palm trees in in Vermont. I've acknowledged the advantages of live rock, and I recommend it, but it's not the only way to get good water quality. The often repeated statement: "bio-balls are a nitrate factory" seemed irrational to me, and after carefully studying the topic I concluded that, if done correctly, there's no nitrate problem (but that's another thread), and there are a few advantages (great gas exchange, inexpensive, more open space in the tank). My bimac was nearly full grown when I caught it 16 months ago, so it is probably about two years old. That is much older than most captive octopus ever get, so my water quality is obviously at least sufficient.

I think bio-balls might have a few properties that are particularly suited to octopus. If you feed an octopus a chunk of meat every 2nd of 3rd day, like I do, rather than a little bit every day, like most other tanks, then a bio-filter that can quickly handle sudden large increases in ammonia (like a wet/dry filter) is an advantage.
 

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