More DAS troubles

[Iostream]

Okay, I have replaced the DAS pump on my 70 gal with an H39 with a Mag 3. It is almost too powerful for the overflow box, if the water level does not almost completely cover the intake slits, the pump will begin sending water out faster than it goes in. This however is not the real problem, I know it happens and just have to keep up on my top off. The real problem is air bubbles, my tank looks almost milky because of all of the air bubbles the new pump is putting out. Is this because the pump is pulling water from the skimmer too fast, before the air bubbles can rise? I have removed both DLS rolls and propped up the Mag 3 on a piece of 1/2" PVC with a 4 way in the middle allowing it to intake from 2 of the 4.. the water level is well above those intakes. I do still have the DLS if I should put the one back in under the Mag. Any ideas on this?

thanks,
Iostream/Justin

[Iostream]

Well it must have been my plumbing, all is better now that I put the old DLS roll back in (just one of the 2) and went to the DAS plumbing. the current is incredible though, It seems to be moving much more water than my Penguin 1140 which is supposed to be 300GPH, so going to have to work out the current a bit, as right now everything is swaying towards the filter intake.

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[DAS Dude]

I've been running a 140 gallon room-divider DAS system since about 1992. I don't want to sound like an expert, but I would like to share my experience with you.

I still use both DLS rolls (only washed in R.O. once), I use the denitrification chamber and the original protien skimmer. I NEVER do water changes, I add R.O. topoff water daily (approx 1 gal/day) and add supplements irregularly. My tank has about 130 pounds of live rock, 6 fish (all 4" or less), +/- 10 corals (LPS and Soft), and a sand bed which ranges between 1/2" and 2". I use about 100 red-legged hermits and 50 margarita snails to control algae and clean the rocks. The only modifications I have made to the original system are:
1. Changed the flourescent lights to 2-250 watt 5500K metal halides (the tank now has no lid)
2. Changed the pump returns to homemade PVC spraybars
3. Added 4 powerheads to the tank.

With that being said, my ammonia and nitrites are at 0 and nitrates barely register. PH remains stable, crabs and snails spawn regularly and all corals are growing nicely.

My only advice to you is to match the original design pumps as close as you can. These tank systems were designed for long-term success. If you have any specific questions I might be able to help you with, please email me at polleydd@hotmail.com.

[Iostream]

Well with the Mag 3, the skimmer seems much more effective, of course my existing DAS pump was dying, and barely putting through any water flow at all. My biggest decision to replace the pump with something else was the fact that tis was my second DAS pump, and it needed to be replaced as well. I wanted something that would be a little bit more reliable for me. I probably just had a bad run, as I have not heard of too many others with pump problems like this.

As for the DAS filter system, the skimmer has pulled more out in the past couple of days than it had in the past couple of months... The tank seems much healthier. Once I get the current worked out so that the things look more natural I think I will be happy with the filtration. Right now my Pulsing Xenia seems to be leaning towards the current filter intake.

I am however working on an overflow design for the DAS system, simply because I want to add a refugium to grow more food for my tang (IPSF Tang Haven), and to hopefully get a good solid pod population for a possible mandarin goby addition. So far with the testing I am doing, it seems like I have a working design, just need order the pump now that I have it sized. with the limitations of the slit in the back, it is a fairly low volume overflow, but should suit my refugium needs well.

Of course this may all be unnecessary, as I am sure my wife will want the tank turned into a FOWLR once I get the bigger tank :) Still, it is fun to mess with.

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