Auto top off help!

[TheAquatard]

How's it going? I got an auto top off, I forget the brand but its the diy kit, anyway I put it together and it functions perfectly. The problem is that my salinity keeps dropping because the water level in my return keeps dropping. I think the problem is in my herbie overflow system, this mysterious disappearing water is getting lost between my full siphon over flow and the emergency overflow. Any ideas? Thanks

 

[Randy Holmes-Farley]

Sorry, I can't understand what you mean. Where would the water go? Is it leaking out onto the floor?

 

[TheAquatard]

I'm guessing the water is betwen the lower full syphon overflow and the higher emergency overflow in the dt tank, no leaks

 

[TheAquatard]

Perhaps my syphon over flow is dialed in too perfectly?

 

[TheFishMan65]

Does the water level in the overflow change? How big a tank? How big an overflow?

 

[TheAquatard]

The two over flows are basically a 90 degree occur joint facing up. I'll explain better. The full syphon overflow is cut about 2 cm shorter than the emergency drain. I believe my missing water is in the 2 cm difference between the over flows.

 

[TheFishMan65]

That is an inch of water. Say the over flow is 10 x 4 that is 40 inches or about a 1/6 of a gallon. Unless you have a small tank I can't see that much water affecting the salinity. What does it change by?

 

[HV1990]

Not to Hijack but what does salinity travel do to a tanks parameters?

 

[Randy Holmes-Farley]

Not to Hijack but what does salinity travel do to a tanks parameters?

Everything except pH will rise and fall linearly with salinity. Same for specific gravity, if that is how you measure salinity.

So if the water is at 34 ppt, and it is allowed to evaporate down to 36 ppt everything will be 36/34 times the original numbers, or 1.06 x the original numbers. For alkalinity (8 dKH --> 8.5 dKH); for magnesium (1250 ppm --> 1324 ppm).

So if the water is at sg = 1.024, and it is allowed to evaporated down to sg = 1.026everything will be 26/24 times the original numbers, or 1.083 x the original numbers. For alkalinity (8 dKH --> 8.7 dKH); for magnesium (1250 ppm --> 1354 ppm).

 

[shaggss]

If you only have an inch or so in height difference between the main (full syphon) and emergency and you have no ATO, then that is your problem. The Herbie needs a bit more than that to allow for fluctuations.

For the Herbie to work properly you need:

1. About six inches in height difference between the main (full syphon) and emergency drains.

2. A gate valve on the main drain. A ball valve will work but a lot hard to dial in.

3. Most importantly an accurate ATO. You must keep the water level in your return at a constant level otherwise the water level in your weir will fluctuate too much. And you will have issues like you are now.

I run the Herbie and it's brilliant. I have not adjusted it in over 6 months. It is super quite and produces no micro bubbles. So long as you have the basics covered it is set and forget.

HTHs!

 

[TheAquatard]

Thanks shaggs I kinda figured it out myself. What was happening was there was no water going into the emergency drain. I guess the full syphon was handling just a tiny bit less than the return was putting out. So over time the water in my return would start to fill the gap between overflows. I let the top off do its thing with sea water and things seem to be running good now.

Just a heads up to anyone reading this, the gate valve makes everything so much easier on these systems. I've used a ball valve in the past and it was just horrible.

 

[TheFishMan65]

Are you topping of with sea water? It should be RO/DI since you are handling evaporation and salt does not evaporate.