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Do I ned to cover the overflow box??????


Nov 24, 2002
upon viewing my 55 gallon setup, I realized that the overflow box could present an avenue of escape. If the octo went into the box he/she could zip right up the siphon tube into the overflow box :x . Has anyone had a problem with this?? I guess that I could try to cover the overflow box with net material, but I'm not sure if that would affect the flow or if its necessary. I've attached a pic of the tank. (I have 50 lbs of live rock, but it seems a bit sparse so I'm going to get more today) Thanks
I've also included a pic my my DIY wet/dry filter. I built the bio-tower from acrylic.
Hi Lawfish

yeah, i think you should try to cover all escape routes. Perhaps using sponges would be the way to go? i have also torn up old net curtains and used them with some success.

Early last year I 'lost' a baby Octopus that looked like filosus. My best guess was that it managed to get into the sump and from there into the cuttlefish tank as they were filtered on the same system. it wouldn't have lasted 2 mins in there. Its either that or the dog ate it! The wooden floors in my house would make finding an escaped octo very easy. But the point is that it must have gotten out via the overflow into sump!

Remeber that base rock like tufa or ocean rock or even clay pipes and pots and stuff like that can fill up an aquarium of suitable octo hiding places too. I think that LR looks way better but sometimes it is just beyond the budget :frown:

Nice filter, what are the dimensions on that?


I will attempt to cover the overflow box with net material and I'll let you know how it works out.

As for my DIY filter, the sump is just a 20 gal tank. The bio-tower is all acrylic measuring 10 1/2 " wide by 24 " high by 12" deep. the bio-chamber holds approx 5 gallons of bioballs. I also have a removable drawer under the biochamber which holds carbon. I may use some polyfilters there as well. The whole thing only cost me approx $110 including the magdrive pump. As you can see from the pics I haven't installed an in sump Skimmer yet but I am working on it.

I actually put about 15 - 20 lbs more live rock in the tank yesterday. I have attached another pic. Do you think that I am close yet or should I get some more. I did set up the rock so that there are plenty of caves and hiding places.

Another subject, one of the Mollies that I am using to cycle the tank gave birth yesterday. quite cool actually. I tried to take some pics of the little fry but they move too fast. cute little buggers.
Hi Lawfish,

Since I need to cover my overflow box too, I've been scouting for a good material. Some of the finer-meshed plastic netting that some veggies come in (cluster tomatoes, for instance) looks very promising, and there's quite a variety available. Has anyone else used this material? (It would have to be cleaned.)

Impressive DIY filter!

Have you tried net material yet? I thought that it might be a good choice because it is already in the correct shape to slip over the overflow box. I am going to try cutting the material off of a larger (7" ?) net and slipping it over the whole overflow box. I'm not sure how to secure it. Maybe a plastic cable tie or something of that nature. Hmmmm.

Well let me know if you figure out something that works well and I'll keep you updated.
That sounds like an interesting idea. I have plastic fishline to lash the net material to the drain holes at the top of my overflow compartment. This is the best I've been able to come up with.

What have the rest of you been using to cover the overflow (and secure the cover)?

Hi Nancy!

I have been using good old duck tape for years to seal covers. Sticks great but looks a little odd! As to my over flow box for the protein skimmer, I cut some extra plastic that comes with the hood to fit really closely to the flow. I like the idea of a netting. I've been worried that Hermin still has access to an avenue of escape, but in the 4 months, he's never gone near the flow. Anyway, I am going to try the netting!

I havnt tryed it yet cause my tank is cycleing but I am planning on useing those course buffing pads that are used on floor buffing machines they are very ridgid and can be cut to the right size and pressed in . Someone who runs a green house and pond suply had told me about them being a good pre filter for my pond
Hi Carol,

About that duck tape - are you using it underwater, too?

I found a hardware store that sells 15 different colors of duck tape!


Hi Nancy!

Just around the lid to seal the tank! and to cover hoses from my eheim. Never used it inside! I figured as long as it's not in direct contact with the saltwater, should be safe to use. But I'm not possative on that. Just know I've used it to seal tanks since my first octopus, which has to be at least 15 years ago! Would be curious to hear what others have used and if it's known to be something I shouldn't be using????

All I know, is I've bought the strongest packing tape, and it doesn't stick cause of the salt. Duck tape sticks through everything!!! (did you know recently in our home paper, they talked about duck tape as a cure for warts??? :yuck: Amazing what people do with it!!!)

Carol :smile:
I had another idea to cover the overflow. I've seen little mesh hang in breeder tanks . They are basically a little cube surrounded by mesh. One of them might be a good size for the overflow box. I'll check around and let you know. :biggrin2:
Lawfish a good way to make more hiding spots with little LR is to take a clay pot or whatever you please then stack up the rock around it. Takes less rock farther.
Overflow cover - It isn't pretty but it works

Hello all:
Well, I finally covered the overflow box. I used net material held in place with plastic cable ties. It isn't very pretty but it seems to be working great. See attached pictures. I hope that this is of some help :shock:

If anyone has comments on how to improve my design please let me know. Cheers and a happy and healthy new year!!! :biggrin2:
Looks fine!

I realised ages ago that the surroundings of an octopus tank dont always look very pretty! LOL The designers of skimmers and overflow boxes just dont take octopuses into consideration!!!! :lol:

I'm sure that it is a necessary prcaution because 2 of the mollies that I am using to cycle the tank ended up in the prefilter box outside of the tank. If they were swept in against their will then an Octo would likely find his/her way through the siphon tube. :shock:

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