Combining Tanks

[CanadianReefer]

So...

I have a several separate systems set up. I'd like to combine 2 of my tanks - a 300g system and a 100g system, in an effort to reduce the amount of plugs I use and to have everything hooked up to the same computer (I'm old school and still have a reefkeeper). Additionally, while the smaller tank houses some fish that simply did not behave in my main DT (like a lemon peel angel who ate all my corals), the idea is that it is a backup tank in case I ever had an emergency in my main DT and needed some place to put my fish and coral quickly - so having the exact water parameters would be a bonus.

My husband will soon be expanding my fish room, which will give me even more maneuverability, so now is the time to figure it out. It seems like it could be as simple as switching which return pump goes into which tank. However, I wonder about flow rates. My 300g system has 2 overflows and my 100g system has 1 overflow. They are located relatively close to one another, so I might lose a bit of flow with a slightly longer pipe, but I wouldn't figure it would make too much of a difference.

What if I were to keep one return pump on the 300g returning to the 300g, then switch out the second return pump on the 300g to go to the 100 g, and vice versa with the return pump on the 100g going to the 300g.

Does this sound like something that would work, or end in nightmare?? Each of the pumps are rated for 1900gph, but of course, the further away, the less you get.

 

[Mandelstam]

What if I were to keep one return pump on the 300g returning to the 300g, then switch out the second return pump on the 300g to go to the 100 g, and vice versa with the return pump on the 100g going to the 300g.

This was just a little bit too confusing lol. Not sure I follow along. How many return pumps do you have running? And with overflows, do you mean 1 overflow = 1 drainpipe?

 

[CanadianReefer]

This was just a little bit too confusing lol. Not sure I follow along. How many return pumps do you have running? And with overflows, do you mean 1 overflow = 1 drainpipe?

On the big system, I have 2 separate overflows (yes, 1 overflow = 1 drain pipe) & 2 separate return pipes - both with their own return pump. On the smaller system, I have 1 overflow and 1 return line with 1 return pump.

In total:

3 overflows (drainpipes)
3 return pipes
3 DC return pumps at 1900gph each

 

[CanadianReefer]

and the tanks are about 8 ft away from one another

 

[Mandelstam]

On the big system, I have 2 separate overflows (yes, 1 overflow = 1 drain pipe) & 2 separate return pipes - both with their own return pump. On the smaller system, I have 1 overflow and 1 return line with 1 return pump.

In total:

3 overflows (drainpipes)
3 return pipes
3 DC return pumps at 1900gph each

If the drainpipes all end up in the same sump which also feeds the return pumps I don't see why it shouldn't work.. But if you are depending on one pump to pump water into another system and then have a second pump returning the exact same amount back to the first system I think you might have a problem.

 

[CanadianReefer]

I have 2 sumps. However, I suppose I could just reduce it to one. I just thought the extra water capacity was an added bonus.

 

[Jlentz]

I’ve got two 90s plumbed into a single 60gal sump. One return pump on a manifold to return water to both tanks. Drains are a herbie setup.

 

[Mandelstam]

I have 2 sumps. However, I suppose I could just reduce it to one. I just thought the extra water capacity was an added bonus.

If you can place the sumps next to each other and connect them that would sort it out. Maybe turn one of them into a fuge?

But if you pump water from one sump into a tank that drains into another sump you have to EXACTLY match that flow from pump no 1 with pump no 2, and that's next to impossible.

 

[Desgada]

Yeah your best bet would be to do one of two things:

1. Take out one of your Sumps and combine the two to create a loop that eventually will completely mix and balance your tanks water. (If you do this the best bet would to be try and match parameters as best you can first.)

2. If you want the extra water from the second sump have it sitting higher than "sump one", and draining into "sump one" with all three return pumps in "sump one."

Another nice thing about the second setup is it gives you room to put in a bigger fuge or reactors or what have you. The only thing that sucks is if your using a top of the line acrylic sump. You would almost have to drill the second sump and place a bulk head about 3/4 of the way up so it can drain without restriction.

Alternately if you wanted the extra space you could get a cheap 20L and drill that as your second sump.

Sorry I was planning as I was typing. But draining one tank into another to make the loop, don't see that working.

 

[CanadianReefer]

I was worried about the flow rates and how easy it would be to match, but I think you're right - next to impossible.

The 2nd sump is under my tank, so for me to access it and get it out (to put it in a higher place) I'd actually have to drain the tank and take apart a portion of the stand. Maybe I'll just slap on an HOB filter and use it as a separate frag tank instead...

My main sump is 80g, so it's a good size and I have lots of extra room for extra equipment. The fuge is 20g within the sump and could be expanded to nearly 40g if I wanted. I just have an empty 20g slot in case I wanted to add extra equipment in the future. I filled it with rock rubble for the time being.

I think I'll just run everything out of the same sump. It will be a little tricky to fit 3 return pumps into the return pump slot, but other than that, setting it up shouldn't be much of a challenge....

Quick question - this 2nd tank contains a lemon peel angel who had to be taken out of my DT for eating all my corals. As such, I filled his tank with nothing buy softies because he won't eat them. This means that I have a lot of chemical warfare and run extra carbon. My DT basically has no softies except a Fiji yellow leather. All this to say that I wonder if combining the tanks will have a negative impact on my SPS and LPS in the main DT? If I run a good deal of carbon, should I be okay??

 

[Desgada]

The amount of water you have in your main tank should make the chemical's unimportant, but if you want to be safe you could always use more carbon and slowly decrease it over time to see if there is any effect. I really don't thing it would be an issue in a 400+ gallon system though.

 

[CanadianReefer]

The amount of water you have in your main tank should make the chemical's unimportant, but if you want to be safe you could always use more carbon and slowly decrease it over time to see if there is any effect. I really don't thing it would be an issue in a 400+ gallon system though.

That's what I was hoping to hear