Auto Water Change - 4L Pico

[Jellyingabout]

Hey all,

 

So after 3 years without a tank i'm finally "easing" myself into it with a 4L pico set up plus a few gadgetry things.

 

I live on the coast and the water here although a bit high in nitrates is generally very clean. I'd like to set up two large resovoirs under my pico one for fresh SW which i will drip feed into the sump.

 

At the same rate fresh SW drips in, i'd like system water to drip out the sump into the second resovoir.  But how do i match the rates without a peripump £££. Any ideas?

 

Cheers,

Aaron

[Muraki]

I would do a separate overflow where it can overflow at the rate water drips in. 

[morecoffee]

If you added an overflow (two for safety) to your sump the old water should naturally drain out at the same rate you are bringing water into the sump from your fresh SW.  If your fresh SW is higher elevation than your sump you could use something like a drip acclimation tube and not use a pump at all.

 

I'm not sure how baffles would affect this, but I would want my waste water to leave near where water enters the sump (no need for clean it if it leaves the system) and have my new water come in near the return pump in my sump.

[Jellyingabout]

Great idea, i could run a cheap irrigation pressure regulator out of the Fresh SW tank to avoid drip rate being too high when the resservoir is full to the top.

 

But by using an overflow would i loose all sense of evaporation in the sump? since the levels in the sump would now be constant?

[morecoffee]

If your reservoir is covered and weekly water change turn over is fairly high I assume your salinity would increase very slowly if much at all due to the high exchange of water.  You could test it then dilute your res with a little RO water down to 1.024 to see if it keeps it stable without a top off.

[Jellyingabout]

An auto water change comes from my deep ingrained laziness. Removing one automated aspect (the auto top up) in place of another feels poo. But you're right it would be much much easier  

I'm probably going to see more fluctuation in salinity just from using NSW anyway

[Jellyingabout]

How about the Jebao Dosing pumps? Would they do the trick?

[Beer]

There is a company that makes a dual ATO and AWC unit for around $200.

 

The system has two sensors. Typically maintains level at the higher sensor like a traditional ATO, but will drain to the lower sensor and refil to the upper sensor based on the programmed schedule.  I don't recall the manufacturer, but  a quick search should get you results pretty quickly.

[Jellyingabout]

I think its the auto aqua AWC, its a bit out of my budget after tax to the uk :/

I think i may try the jebao dosing pump, if it doesn't do the trick at least i have a dosing pump

[Beer]

Aren't those dosers close to $200 anyway?

 

I would try mounting two heads on the same motor so they run at the same time and at the same speed. They are not exactly known for being the most precice units, even after calibration. Draw from the return area and add to the center or return section.

 

I would be sure to check tank salinity a couple times a week just to be sure.

[Jellyingabout]

Not quiet, the Jebao 2 head doser is £40 here so around $56

[Archetype]

Honestly, I would just do a 100% water change every week.  I had a 1.5 gallon office pico and it took me all of 5 minutes to scrub the glass, stir the sand, empty the tank and fill it back up.  Corals, maxi mini anemone and crab didn't seem to mind.

[Jellyingabout]

Thats how i ran my last pico and i went fine with great SPS growth, but this time round i'm aiming for a crocea clam, and plenty of fan and coco worms, with a tank so invert heavy I'm wanting everything as constant and gentle as possible.

[Jellyingabout]

Also i ideally would like to gather up enough NSW to keep me going for a few weeks only collecting it on the flowing Spring High Tide, so ill be storing it anyway, and if im storing it i need to keep it flowing to avoid bacterial growth, and if im storing it and oxygening it i might as well take the extra step to drip it in

[morecoffee]

On second thought if your drip rate were for some reason not exceeding your evaporation by a certain ratio (not sure the ratio) then salinity easily could build up.  Have you thought of maybe doing an automated water change, but not continuous.   Possibly put a weak pump on a timer to run x minutes x times a week and have your auto top off sensor set right below the overflow level.  

 

I'm curious how big you plan for your sump and NSW reservoir.  Even with agitation/o2 I'd be curious is NSW would change in an undesirable way over the course of a year.

 

[Jellyingabout]

Well i could grab fresh NSW every spring high tide, and the Spring-neap cycle is around 14 days, so I have the oportunity to grab pristine water every fortnight. 

 

My sump is going to be around 30L and the resovoirs are a pair of 32L fermenting buckets that have given me a good few glugs of homebrew

[Beer]

I've only seen the 4 head dosers that were closer to $200. Didn't realize they had 2 head for that cheap.

[Jellyingabout]

Even the 4 heads are only £56=$79 on the uk ebay also  a bit of a steal really.