Skimmer Impeller mods

[Mr. Fosi]

I have a skimmer that pulls wet skimmate but I want it to do better.

 

I am contemplating a maxijet mesh mod but I don't have the mesh used here. I have another type of mesh that I've been using as shade but is is made of a much thicker plastic with fewer strands.

 

I have a couple bioballs sitting around as well so a needlewheel is also an option. I tried drilling the impeller of another powerhead but it crippled the powerhead's ability pull in air.

 

So here're my questions:

 

- Which do you think is best for making tons of tiny bubbles?

- If my skimmer is intended to be run with a 211 gph pump with a standard impeller, which of these mods will will bring an MJ1200's output (295 gph)down far enough without crippling it's ability to suck in air?

[distantfire]

My answer to your first question would be the mesh mod. Because there producing ton's of bubbles in only a matter of a few hour's.

And I have three answer's for your second question. {1} None of the above mod's will bring the MJ1200's output down far enough. {2} If all you have is the MJ1200 and you want to slow down it's flow. Put the impelar on the flat corner surface of your anvil. Take a razor blade and trim off the end's of each impelar blade. It's important that you trim each impelar blade to the exact same length. I'm sure you've seen people that have cut the blades off of there impelars to slow down the water flow. But cuting the blades completly off can throw the impelar off it's axis. Of course then two thing's happen {1} It shorten's the life of the pump and {2} it wreak's the impelar making the pump unuseable until a new impelar can be purchased. And I know using a dremel to do this job is faster. But if you havn't done it before use a razor blade and the flat corner surface of your anvil. Because the razor blade will give you a precise 1/32" clean finished cut. It's a time consuming job for two reasons {1} Taking off 1/32nd of an inch from the end's of the impelar blades. And {2} You have to visualy compare your MJ's water flow output. With a slower running water pump each time you trim down the end's of the impelar blades. So that you don't make your MJ's water flow's output run to slow.

 

And {3} If you had a MJ900 rated for 230 gph it would be easier and cheaper for you to mod. Because it's a lot closer to what your skimmer is rated for.

 

Edited because I had to reread your question's over one more time.

[Mr. Fosi]

Glad to have you posting in my thread dfire; you always have great ideas.

 

Take a razor blade and trim off the end's of each impelar blade.

 

- So you mean to shorten the blade length rather than make them "thinner" like the guy did in the above link (and pics below)?

- Do you think that shorter is better than thinner and why?

- Do you think that making the blades thinner would give me a little more room for error?

 

 

... If you had a MJ900 rated for 230 gph it would be easier and cheaper for you to mod. Because it's a lot closer to what your skimmer is rated for.

 

I know.

 

Not only is it much closer with regard to flowrate but it also consumes a lot less energy; 8.5W for the 900 and 20W for the 1200. 20W is fully half of what my Q1 3000 consumes. The other pumps I have are rated no higher than 175 gph, with the exception of my Mag 5 & 9.5.

 

You don't happen to have a MJ900 that you'd sell me, do you?

[Mr. Fosi]

The mesh I have looks a lot like this:

 

 

The holes are diamond-shaped and the holes measure 4 mm x 5 mm between the diamond points.

[cmador]

I did the fishing line mod on the impeller for my octopus 110. From what I've read, the mesh mod is too much for this particular skimmer. I circled the impeller three times and I've been happy with the results. I used 8 pound test line and it took me just a few minutes to do the mod.

[Mr. Fosi]

Yeah, isn't your skimmer already a needlewheel?

[Mr. Fosi]

Perhaps I could do a combo of the DIY bioball needlewheel and the fishing line mod?

 

I have some 6 lb test line and I have a couple bioballs...

 

 

 

 

I'd still have to cut the impellers down to slow the flow. Now I really wish I had a MJ900.

[distantfire]

To make the blades thinner would require more precise work on your part to do. And I couldn't sit with a good concious and tell somebody to do it that way. If they've never worked on any of there impelar blades before. Your margin for error does increase when you try to make the blades thinner. Because it's easy to accidently break off one of the blades when your sanding them down.

And I'm sorry to say that I can't part with my MJ900 right now because it's in a tank. Otherwise I would gladly send it over to you. The only extra powerhead I have on hand right now is a 550 Penquin and it's a few year's old already. But it still run's like a champion and I use it to mix SW every couple of months.

[Mr. Fosi]

I am using a 550 to power the skimmer right now and it skims wet but that's it. I thought about stepping up to the 660 I have laying around but it is only an additional 50 gph and probably wouldn't really improve things.

 

I guess I'll just stick with the MJ1200 mod for now and eat the extra energy usage. Right now, I'm planning to sand down the blades shorter rather than thinner. I'll probably use one of our vernier calipers to make sure they come out the same length.

 

I've gotta take another look at the bioball I have sitting at home and determine whether it will work for this mod. Whether it works or not, I'll probably try some form of the fishline mod.

[distantfire]

Let me know how that fishline mod work's out for ya.

I got a 2.5 out in the garage right now with a 2.5 soon to be fuge tank. I put 4 coats of krylon fusion satin blue on the back of the tank and then covered the satin blue with 4 coats of krylon fusion satin black. The external overflow box is 3 1/2" wide and 4 1/2" long. The bulkhead and 1" pvc pipe durso were a tight fit. Because the slot I made inside the black trim on the back of the tank is only 1/8" wide by 3 3/4" long. I made the dust cover for the box out of window glass and drilled a hole in it for the end cap to come thru. I snaped a couple pic's earlier today I just havn't checked them out yet or put them in my members gallery. I still need to paint the dust cover satin black. And make a divider for the 2.5 fuge I'm going to make a L out of eggcrate and put that L on top of the divider. That way I will have a ledge to lay my fiber floss across. And that's my latest idea for the top of a divider to keep the return pump clean.

I'm also in the middle of doing a 70 watt MH mod. I'm just waiting for the big brown truck to deliver the new ballast.

[Kraylen]

Oh man +1 on this thread. I got maxi jets laying around hell yeah.

[Mr. Fosi]

I've always liked your pico tanks; you have made some unique setups.

[lilredneckman]

I want to see more on this bio ball mod. I think it is a great idea.

[cmador]

I forgot to mention that I did this mod http://www.cpraquatic.com/forums/viewtopic.php?t=2875 a while back on my MJ1200 for my old bak-pak skimmer with good results.

[Mr. Fosi]

I like that venturi mod! I was playing around tonight trying to work a cleaner one out but I just might coop that one!

[Mr. Fosi]

Alrighty, so I am still stuck with using an MJ1200 but the good news is that I have some new impellers + parts for it coming in the mail thanks to scottyreef.

 

Because the new parts are coming, I decided to get brave and mod one of impellers that I have which is likely to quit working soon anyway...

 

I'll have pics up later tonight or tomorrow but here is a short list of what I did:

 

- sanded impeller blade down shorter

- sanded blades thinner as well

- attached an acrylic disk and some shading mesh with 6 lb test fishing line

 

I just got done testing the flowrate and it looks like it is pushing somewhere between 115 gph and 168 gph. I didn't have a clock to do the per sec counts, which is why the estimate is so variable. I will test it better tonight or tomorrow.

 

If I did cut the flowrate down that much, I am not going to use that impeller because there is no reason to waste the energy to have the same flowrate I can get with a penguin 660.

 

I have another, less destructive mod in mind but I'll have more on that when I come back with pics.

[distantfire]

I was thinking that a less destructive and simpler way to slow down the output water flow of a MJ. Would be by puting a thin arcylic disc over most of the input. You could use masking tape to hold the small disk over the input while your checking the waterflow's output. After you get the waterflow that you want take your fine point sharpie and mark the input's opening on both sides. Apply some Weldon or Oatley to the disc and let it dry in place.

At least that way you wouldn't have to mess around with the impelar blades.

 

Today I bought a fountain pump it cost me a whoping 7 dollars because it was on clearance. It doe's 130 gph and has a 1/2" ID. output. I'm going to use it for my 2.5 gal fuge's return pump and just let it run until it dies. Tommorow afternoon I'll stroll over to Menards and see if they have any 1/2" ID. CPVC and 1/2" 90 deg elbows.

[Mr. Fosi]

I was thinking that a less destructive and simpler way to slow down the output water flow of a MJ. Would be by puting a thin arcylic disc over most of the input.

 

I have read in several places that restricting the input to magnetic impeller pumps is a bad idea because it can lead to cavitation and premature pump failure. The same is not true if you switch the restriction to the output... Or at least so I have read. This is why people are always counseled to add ball valves to the output of a pump who's flow they want to reduce.

 

Today I bought a fountain pump it cost me a whoping 7 dollars because it was on clearance. It doe's 130 gph and has a 1/2" ID. output.

 

I have a couple pumps of that size and output as well. They work great for waterchanges and two of them were used in different pico tanks for water movement.

 

What kind of head will the pump have to push after the PVC length, elbows and height? Think you'll still get more than 100 gph out of it?

 

*** IMPELLER MOD UPDATE ***

 

The following pics are of a setup that didn't work properly.

 

The acrylic disk. I wasn't thinking when I started drilling the holes so they aren't balanced as they should be.

 

 

 

 

The other parts (sans fishing line), including the trimmed impeller. I used a vernier caliper when I was sanding the impeller blades so I know that they are all the same length/height.

 

 

 

 

A couple views of the disk + mesh attached to the impeller with the fishing line.

 

 

 

 

A view of the whole contraption.

 

 

 

 

After two tests, I was unhappy enough to take it apart. It severely restricted the flow and it was incredibly loud. Had I decided to put up with the noise, virtually impossible to do unless my wife and I were deaf, I am sure the pump wouldn't have lasted very long without breaking.

 

I tested the pump with the naked impeller and it isn't any louder than other MJ1200's and the flow was (of course) greatly improved, so I am sure it was the other additions that ruined the game.

 

I did manage to find a filter sponge that looks more like the "mesh" that others have used for mesh wheel mods but I haven't tried attaching it to the impeller yet because I am afraid that it would be a further waste of time.

 

I have a couple other mods in mind: the bioball mod who's pic I posted before and a threadwheel.

 

Unfortunately, I don't have the style of bioball that most people have used for the bioball mod so I am not sure I will be able to make it work. The threadwheel looks fairly doable but I am not sure that I won't permanently jack up the impeller. I'll probably wait until the MJ parts from scotty arrive and rethink this little project in light of the new parts.

 

I'll hopefully have another update for this thread later in the week.

[eklikewhoa]

I have done a few mods on the CPR bakpak and my PM Hot1 which both had MJ900/1200's on.

 

One I drilled the impeller blade and used fishing line to tie some plastic cross-stitching grid to like you did on yours Mr.Fosi but sans the plate. Worked like a champ!

 

The second was done in the same fashion but I added the venturi that is drilled right above where the impeller blades sit on the MJ. and that really increased it a great deal!

 

I have tried doing the bio-ball needle wheel mod but everytime I finish the impeller is unable to spin with it installed.

[TheWAND]

fosi, get a hold of a couple bioballs and try the NW mod for the MJ. I want to see how that works

[distantfire]

Well I had her running earlier today and the overflow box worked just fine. But the bottom right corner of the display tank has a pin hole leak. So I decided it would be easier to start over with a new tank. I'm leaning toward's buying a 5.5 next week for my new display tank.

 

Because of the black trim around the bottom of the 2.5. I can't see where the leak is starting from. I might have accidently punctured the bottom seal when I put in the cuting board. Or I might have chiped the bottom moving the tank around when I was working on it. In any case that 2.5 is a goner and I'm going to start over again. I measured the pump's height from the output to the top of the first 90 deg. elbow that was 19". I'm happy with the pump's output at 19" I would say that it was still pushing out at least 100 gph.

[skrezyna]

Is a modded MJ1200 impellar the right one for the stock Octopus 100-BH stock pump?

[reefer123]

on my cpr bak pak i mesh modded the maxijet on an acrylic dick and drilled out the venturi

[not_sponsored]

on my cpr bak pak i mesh modded the maxijet on an acrylic dick and drilled out the venturi

 

[Mavvy]

 

Yeah...that's GOTTA hurt...