Merging a 210 Gallon and 105 Gallon System into 1 Sump - Recommendations

[Danny McElroy]

I am planning to merge two systems into one sump filtration for the purpose of maintaining only one set of parameters and am curious if there are any recommendations or challenges I should be anticipating and planning for? This is not a plumbing question, but a chemistry and stability question. The larger system is 260 gallon (including sump) that is 100% SPS running very stable for about 2 years with great growth and color, and the other is a 105 gallon 1 year old LPS and softy only tank that has stable parameters but has consistently had hair algae and bubble algae growth. Both systems are running BRS Ca, Soda Ash, Mag, and Kalkwasser, and Red Sea Trace Elements, and Acro Power Aminos. Both have chaeto refugiums, roller mats, and tropic Marin bio pellets for nutrient control. I feed the systems very heavy and keep phosphates down below .1 with BRS GFO and Carbon. pH on the larger system is stable between 8.29-8.33 and the smaller system 8.17 to 8.21 using the Apex on both systems to dose kalkwasser to keep the pH stable. Using trident controlled dosing on both systems alkalinity is stable at 9 dkh, calcium is 450-480 and Magnesium is 1380-1420. Both systems have skimmers with air lines running outside. The larger system has a 40 watt UV sterilizer, and the small system has a 25 watt. I think that's everything.

 

[00W]

Water is water and it will merge and you'll test.
In a bit,with a few adjustments on your part,parameters in both tanks will be where you want them to be.
You'll understand how much you need to dose now with more water volume.
Bubble algae may go from one to another as it's want to do.
I have 2 tanks on one sump, both have the same lighting, and, of course the same water and neither tank is the same.
You seem to have a good grasp on all of this and have everything equipment wise going on so this shouldn't be difficult for you I'm sure.
I won't get into any plumbing issues unless you ask.
Hope that helps.
Joel

 

[Randy Holmes-Farley]

I’m not aware of any special chemistry challenges that will ensue. Many parameters and needs will now fall in between the two scenarios before combining them (alk demand, etc)

 

[blecki]

IMO this just means the tank with the algae growth is your new refugium for the big tank. I know you're not asking about plumbing but I want to know is this two drains / two returns into and out of one big sump, or will they be plumbed into a loop of sps tank -> softie tank -> sump -> sps tank?