21mm/25mm to 16mm/22mm help please

[Markmark]

Greetings all,

I was wondering if its possible to reduce 21/25mm pipework( supplied with my filter) to 16/22mm so I can fit an atomizer to the return.

As I will only need to reduce a section for the atomizer on the return only will this place undue stress on the filter or is it better to replace both intake and return completely.

Thanks

Mark

 

[ceg4048]

Hello,
Installing a reducer as you propose would incur a penalty of an approximate 42% reduction in flow throughput of your filter. It doesn't matter if you only have the pipe diameter reduce at one location versus the entire system of pipework. Anywhere that you restrict the nominal cross sectional area of the pipework chokes the flow (imagine if someone gripped your throat and reduced the diameter of your wind pipe at only one location. Would it affect how much air you could breathe?)

There is no mechanical stress for the impeller or other moving parts, it simply can't deliver as much throughput as compared to flowing through the nominal pipework. You would do better to install a DIY reactor which maintains the nominal diameter. Do a search for DIY CO2 reactor.

Cheers,

 

[RudeDogg1]

Is there not a larger atomiser? I know the up one does 3 or 4 diff sizes

 

[Markmark]

Thanks for the replies guys.

I realised they would be a reduction in flow but 42% is crazy. I think I shall be using my Fluval 205 instead for my atomizer and I can fit a Hydor 300 watt heater at same time. That way I can leave my main filter for filtraton only and keep up the flow.

If I do this Ceg, Shall I remove all media from my Fluval or keep the media intact and have added biological filtration?

Thanks

 

[ceg4048]

Hi mate,
Well if you're just using the 205 for CO2 then you'd want to maximize it's flow throughput as well. I'm not sure what the flow rating of that model is and I'm not sure how big your tank is, but generally you'd probably want to remove all the rock type media and maybe jut have a little bit of foam to break up the bubbles. I'm not sure but you n=might wind up cavitating the impeller or get too much gas buildup if you run it without any media at all - or you might not. It depends on the flow rate, the bubble rate, the design of the filter and the distance between the atomizer and filter. Try both ways and see if you get noise or better gas dissolution one way or the other.

The other thing you have to remember that the throughput is only half the story. You still have to distribute the saturated water evenly throughout the tank. Is the 205 man enough for the task? Again, depends on tank dimensions and the distribution pipework. You definitely want to make sure that the outflow from the 205 does not conflict with the output from the bigger filter. You'll need to wear your thinking cap on this one mate. Maybe if you show some pictures of the pipework configuration we might be able to be more precise.

Cheers,

 

[Markmark]

Thanks Ceg,

Tank dimensions 90x45x45

Allponds 2000ef with spraybar running length of tank. Fluval 205 with atomizer with flow directed into spraybar.
Thats my plan mate
thanks,

 

[ceg4048]

Well, 90 cm isn't monstrous but it's no nanny tank either mate. the effluent from the holes on the spraybar should reach all the way to the front glass with some force. At the risk of sounding redundant, does the 205 have enough muscle to accomplish this? I leave it to you mate.

Cheers,