Possible leak

[BuddyBonButt]

Here's a long one. Please any info helps I'll attach pictures of my setup

So I might have a leak. Last night about 4 cups of water went missing in about 4 hours.

Before this happened, my last recorded salinity was 1.025. And My tank has glass lids that cover the entire top AND a canopy so evaporation is low

Every night for the last 2 months at 9:30pm I fill up the sump with 4 to 5 cups of fresh water to combat evaporation. Last night, at 9:30 I filled the sump with 4 cups of water. 3 and a half hours later at 1am I was messing with the skimmer and heard air entering the return pump due to missing water (4 cups worth maybe more, I don't refil when air hits the return pump so maybe more like 6 to 7 cups!). I shut the system down and checked:

Tank corners
Tank walls
Tank base
Bulkheads and piping
All around the stand

Nothing.

Then I checked salinity to see if it was higher from Evaportation and it was at 1.026 or 27 so I figured that was a good sign.

I checked around the sump. I was playing with the skimmer so there was water on the bottom but I noticed a slight wet spot behind the sump where I wasn't near. So I ripped the sump out and put it in my bathroom and refilled it with tap water and marked the water level with Blue painters tape. 12 hours later there was the expected water loss. Not close to 6/7 cups like last night.

The only difference now compared to the 2 months is I replaced the dual-headed lock line to a single headed lock line. Other than that nothing has changed.

Do you have any idea where I could be missing the leak? Literally nothing in view is wet!

Here's a full list of what the tank looks like


Tank info:
90 gal tank 20 gal sump
I removed the sterilizer weeks ago and it was still consistent to 4 cups a day
78 degrees F.
Normally 1.025 salinity
No livestock
750 gph return pump

 

[stevolough]

You could have a restriction in your overflow line. Is your main display water level the same or is it a little higher then normal. And what style overflow is it?

 

[stevolough]

Also it would take more then a few cups of water to register a salinity change in a setup that size

 

[BuddyBonButt]

You could have a restriction in your overflow line. Is your main display water level the same or is it a little higher then normal. And what style overflow is it?

Main tank level looks normal. I did hear a random gush from the intake bulkhead line but it didn't increase the water level after and I dont know the type of overflow. Sorry. One inlet and one outlet. I'll keep a close eye on the display levels

 

[BuddyBonButt]

Also it would take more then a few cups of water to register a salinity change in a setup that size

Hmm ok. I never really tested it. It seemed to changes by a fraction of a level but I guess I can rule that one out though

 

[BuddyBonButt]

You could have a restriction in your overflow line. Is your main display water level the same or is it a little higher then normal. And what style overflow is it?

That's the best pic I can get. Those aren't water droplets on the outside, the overflow is currently drained

 

[sfin52]

Fill sump and place paper towels around the sump , could put a couple of drops of food coloring on the towel. If the towels get wet the food coloring will spread. This would give you a visual than just a wet paper towels.

 

[BuddyBonButt]

Fill sump and place paper towels around the sump , could put a couple of drops of food coloring on the towel. If the towels get wet the food coloring will spread. This would give you a visual than just a wet paper towels.

First thing I did. It's sitting on paper towels. It's still filled in the bathroom. Completely dry

 

[The Farmer]

When changing out your return line did u accidentally crack the bulkhead see if there is any wet spots by the return

 

[The Farmer]

Is the carpet around the tank wet?

 

[BuddyBonButt]

When changing out your return line did u accidentally crack the bulkhead see if there is any wet spots by the return

No it's completely dry. First thing I checked. I used toilet paper to check for moisture along with a flashlight for shininess

 

[BuddyBonButt]

Is the carpet around the tank wet?

Nope, literally everything is bone dry. I refuse to believe that I evaporated 6 cups of water in three and a half hours

 

[The Farmer]

What is your ambient temperature?

 

[BuddyBonButt]

Fill sump and place paper towels around the sump , could put a couple of drops of food coloring on the towel. If the towels get wet the food coloring will spread. This would give you a visual than just a wet paper towels.

What is your ambient temperature?

Room, 72, tank 78

 

[sfin52]

No it's completely dry. First thing I checked. I used toilet paper to check for moisture along with a flashlight for shininess

Any way that you have a back flow from the tank some place. A wire or hose that is wicking water out of the tank and down the side that is causing a drip. Could be caused by wave maker.

If both are dry it could be a flow issue with the return or drain.

 

[BuddyBonButt]

Any way that you have a back flow from the tank some place. A wire or hose that is wicking water out of the tank and down the side that is causing a drip. Could be caused by wave maker.

If both are dry it could be a flow issue with the return or drain.

Like a highway for water? No all power cables are dry. Flow issue? Where exactly? Nothing seems clogged. Any ideas?

 

[sfin52]

Like a highway for water? No all power cables are dry. Flow issue? Where exactly? Nothing seems clogged. Any ideas?

You may have a restricted flow in drian or the sump. The return chamber isn't getting enough water and thus causing return chamber to run low and create sucking in return pump.

Or the drain has a snail or something not allowing the right amount of water to get to the sump. With durso prob more likely algea than snail

 

[jmatt]

Well, the weather is starting to warm up... have you recently started to use the air conditioning? It could just be more evaporation due to that. If it's not anywhere on the floor then the only place it can go is the air.

 

[BuddyBonButt]

You may have a restricted flow in drian or the sump. The return chamber isn't getting enough water and thus causing return chamber to run low and create sucking in return pump.

Or the drain has a snail or something not allowing the right amount of water to get to the sump. With durso prob more likely algea than snail

No algae no livestock. I pulled the intake out and it's clear. The return has a ton of pressure plus clear tubing shows it's not restricted. I'm at a loss for words

 

[BuddyBonButt]

Well, the weather is starting to warm up... have you recently started to use the air conditioning? It could just be more evaporation due to that. If it's not anywhere on the floor then the only place it can go is the air.

I live in Florida... ac is on constantly set to 72 degrees.