Today is the big day finally buying new pumps

[Avalanche Wolf]

I am finally ordering my new pumps as the old ac402s are just not working or will not come on after a power outage or will just plain stop working. I am torn between to Hydor Koralia 3 and the 4
Hydor Koralia 3 Circulation Pump/Powerhead UL 850 gph
Hydor Koralia 4 Circulation Pump/Powerhead UL 1200 gph

My tank is a 100 gallon tank is 5ft long , 2 ft tall and 16" deep.

Here is a look at my rock work

SPS is marked in yellow and lps and softies and such are in green.All sps corals are centered depth wise and softies and such are center to front.

I currently have 1 402 blowing across the back wall a 402 in the top left corner and the 2x 620 seios facing each other. The return from the sump is via 3300 with a 5ft head in the top left corner so I might be getting 570 gph output on that. The 402s will be leaving my tank as one is already doa at this time.


On one hand I am worried the Kor 4 1200gph will create a sand storm and be too much but on the other hand the 3's at 850 really is not too much more and i will continue to have my flow problems..

I was planning on putting the new pumps where the seio 620s are and moving the 620s 1/3 from the end of the tank on the back wall facing forward. ( the 620s are very weak and very wide dispersal.)

I ran some numbers last night and not sure what to think of them.

Return at 570gph Via aqua 3300 ( 977 gph @ 5ft )
Sieos at 1240gph (Sieo 620 x 2)
was my bas line of 1811

With the HK3s this woud give me a turn over of 35.1x per hour
With the HK4s this would give me a turn over of 42.1x per hour

Currently I have the 402s, return and 620 for a turn over of 22.8x gph ( when the aclears are working and all pumps are clean and optimal that is )

Which seems really high but again that I why I came here for advice.

I tried posting this on the main section and got little to no response so I come to my local fellow reefers.

 

[DMBillies]

I have 2 K4's on the ends of my 90 (in addition to a 1200gph return and a 1100gph CL). I took some adjustment to keep them from shooting sand around, but it should be doable in a 100. I would definitely go with the K4's. Softies and LPS can generally handle higher flow (they mostly just don't require it) and your tank should probably stay healthier overall. FWIW, I'm planning on sticking at least 1 more K4 in my 90 when I change to barebottom and I have a 4th I'm also thinking might make it in there (of course I won't have sand to worry about.

 

[Avalanche Wolf]

Thanks for info Brian !

 

[NeveSSL]

I personally have 2 3's in my 45 with about 300GPH on my returns. I would say definitely go with the 4's. I had SOME problems with sand blowing around, but with the new flow deflectors the Koralias come with and some messing with them, I got it worked out and have most of my sandbed covered with two small dead spots, I think.

Sorry about the horrible picture, but this gives a general idea. My returns are 3/4" to two 1/2" loc lines per side which gives me some extra "pointability".

Brandon

 

[lotsoftats]

go with the 4's I have two of them in my 65 and love them.