HOB overflow and concerns about flooding - Guidance kindly requested

[Juskr6]

Hello everyone,

My name is Justin and this is my first post. I am getting back into saltwater aquariums and I am purchasing an existing 75 gallon reef tank (picture attached). My only concern is the system currently is setup using a HOB overflow system (Aqueon Proflex Model 1 Sump, CPR Aquatic Overflow box, and 1260 Eheim return Pump) and from what I have read, it is recommended to use a drilled tank due to the risk associated with HOB. The seller has agreed to keep the live rock and fish in another tank for a week or two while I get the tank moved, setup and running.

This arrangement provides me some flexibility and I was hoping to get feedback from the community on my questions below.

1. Are HOB systems ok or will I eventually regret not making the change now?
2. If I kept the HOB system, what measures could I take to prevent overflow due to loss of siphon or power loss?
3. Should I risk it and try and drill it myself?
4. Should I purchase a new 75 gallon that is drilled (adding to the overall cost)

 

[mcgyvr]

1) They can be "ok" but a drilled tank is better... Both can fail if not done properly..
2) using a toms aqualifter or powerhead with a venturi option to continually pump water out of he top section of that overflow so that in the event that air bubbles get there the siphon is not lost.. Like this (note I just found this video and only watched the first 10 seconds so I'm not sure if the information is correct or not but I'm going to assume it is for now).https://www.youtube.com/watch?v=JsTirj_6qjA
3)Drilling a tank is fairly easy but you must ensure that the pane of glass you drill is not tempered.. Then you need to get an overflow box/plumbing,etc.. which isn't hard but can be quite a bit to learn for a newbie.
4)Thats your choice..
Personally I have run an HOB overflow.. It never failed on me but came close a time or 2 and I was always worried about it and babying it/constantly checking on it..
I now will only run a bean animal drain system and sleep like a baby at night because I don't worry one single bit about it..
But many use HOB overflows without issue.. You just need to maintain it properly/check on it.. and also ensure that your sump return pump section is small enough that in the event of the hob losing siphon that the pump runs dry before the display tank overflows.. If you do that the risks are basically mitigated..

 

[sde1500]

I would not use a HOB overflow relying on a pump to stay running like CPR does. I do use one from EShopps though and it works perfectly fine. Just need to get the flow rate high enough you see bubbles leaving the U-Tube. I've never had an issue with it restarting. Or getting the siphon going again after taking the tube out to clean. Going on two years with it. So while I do think it's perfectly fine if I did it all over again, which I will with the inevitable upgrade, I will drill. Very much easier and quieter. And perfectly reliable.

 

[Rover88]

Hello everyone,

My name is Justin and this is my first post. I am getting back into saltwater aquariums and I am purchasing an existing 75 gallon reef tank (picture attached). My only concern is the system currently is setup using a HOB overflow system (Aqueon Proflex Model 1 Sump, CPR Aquatic Overflow box, and 1260 Eheim return Pump) and from what I have read, it is recommended to use a drilled tank due to the risk associated with HOB. The seller has agreed to keep the live rock and fish in another tank for a week or two while I get the tank moved, setup and running.

This arrangement provides me some flexibility and I was hoping to get feedback from the community on my questions below.

1. Are HOB systems ok or will I eventually regret not making the change now?
2. If I kept the HOB system, what measures could I take to prevent overflow due to loss of siphon or power loss?
3. Should I risk it and try and drill it myself?
4. Should I purchase a new 75 gallon that is drilled (adding to the overall cost)

1. Everything can fail. HOB is more likely. If its in your means to get a drilled tank, do that.
2. The best way I've found is that in your sump, where the pump is, make sure that the water is low enough that the pump doesn't run dry normally, BUT, there isn't enough water to overflow the top tank. This means in the event the siphon is lost, it'll keep pumping water up top... But with no water returning to the sump, the 'pump section' can be designed to run out of water before it overflows the tank. The advantage? Dry floor. Disadvantage? High likelyhood of burning out your pump.
3. I didnt want to risk it.
4. ... I bought a 75 gallon USED with drilled holes!

 

[heathlindner25]

That's a good way to get the fire department out at your house .

 

[Rover88]

That's a good way to get the fire department out at your house .

Very unlikely.

Once the water gets low enough, the pump can't clear it out of the sump, and sucks a bit of air. It spits and gurgle and churns, but it is still embedded and moving enough water to not get hot enough to burn. There is just a chance of it seizing up and failing, at which point they aren't a fire hazard.

Now if you take a pump, set it on a table, and run it dry... it might burn up before it burns out, if that makes sense.

 

[Juskr6]

Thanks guys, this is amazing support. I of guidance and support is s Lots of great advice and I have some timing issue. Based on what I have read above, do what it takes to get a drilled tank. Which may mean I setup the entire tank and then find a drilled one that fits the custom canopy.

 

[Juskr6]

I wish I could figure out how to post pictures.

 

[ssky]

you can always drill that 75 gallon used tank. Drilling though seems daunting is very straight forward. If you are still concerned take it to any lfs and they will drill it fory uo for 10-15 bucks. If the tank is made by marineland or aqueon the sides are not tempered and you can drill it. Bottom pane is 100% tempered so do not try to drill the bottom. Drill the back pane and install an overflow box. There are some very good overflow boxes available.

 

[Juskr6]

Thanks, i am going to call around to see if any LFS will drill the tank. First place I called said they used to but to much risk.

As for transporting the tank, how much of the 75 gallons of water should I keep? My local fish store sells RO/DI premixed which I plan to use. The seller of the tank was thinking 20 gallons but I was thinking more around 40.