Automatic flow-though water change system

[rickcasa]

Please let me know if this exact system, as I will describe it, is being utilized elsewhere. I'm determining it's effectiveness over the standard 10% wc every 2 weeks.

I want to use a 4x2x2.5 tank as a reservoir. I'm not too keen on the storage barrels and because they take up too much space. This 110 will be divided in the middle with a baffle and both halves will be salty! When one half is inline, the other is busy making rodi and manually mixed with salt when full. This will be ready when the first half is exhausted...and the cycle repeats. With me so far??

My controller will manage the pumps in the salt chambers with float valves. The frag tank, hooked up to the 50g fuge below as its sump (no skimmer), will get the influx of new water at a rate 3 g per day (1% of total volume). This will overflow into the return chamber of the DT sump. Now to get rid of excess old water, I need an overflow which drains out directly to the house plumbing. This I may put in the first chamber.

Any and all thoughts are solicited.

I wonder how many gallons per day is practical and effective?

[mark]

seen few threads people just using a dual head peristaltic pump, a SW storage tank and waste just into the drain. Here's one (http://www.canreef.com/vbulletin/reefcentral.com/forums/showthread.php?t=2349824)from RC. Thing I wonder is worth the effort when people then still siphon out the display and sump to clear the crub that builds up effectively doing a water changes anyways.

[rickcasa]

I've read some of those threads too. But without using dual peristaltic pumps, I think there's an even simpler way using float sensors and the sump's water level.

First I'll drill a drain hole on the sump wall just above the normal water level and this will be plumbed to the house plumbing.

When the Return pump is programmed to shut off daily, dt water siphons down the sump raising the water level and drains out as waste.

In a few minutes, the return pump is turned back on and depletes the chamber level as it fills the DT back up. A sensor will trigger new salt water to be pumped back to restore normal sump water level.

Any issues with this idea?

Ok, so during power outages, a water change will be forced...not such a bad thing.

As for the crud, well I'll vacuum every now and then.

[mark]

well like the other AWC posts just need to handle evaporation so ATO isn't saltwater.

[Bill]

I like the idea but it's lots of work to set up. Level switches, pumps, overflow drains etc. can and do fail. Then there's the programming in the controller-you want to include some code to account for all possible failure events. Also, your system is open to the sewer? And if that backs up? Checkvalves can leak.

I had a similar system set up on my 180 but I feel that I got better results from a single large monthly waterchange so I went back. Live and learn.

Good info here : http://www.reefkeeping.com/issues/2005-10/rhf/#4