Top tank frame replacement on running tank

wings4wheels · Apr 6, 2021

Ok, I have a 150 gallon, 6foot tank and the top frame where the cross braces are has some cracking and is slightly split, most likely allowing a little extra bow. I should have fixed this a long time ago, but didn't. Now I am freaking out a bit and want to replace it. I have already acquired a replacement frame, just wonder if there was a way to swap this out while temporarily lowering the water level in the tank? I was hoping to leave like a 1/4 of the water in, with the live stock, swap it out and then refill. Any advice, especially from anyone who has done this would be greatly appreciated.

mdb_talon · Apr 6, 2021

If it was just an outside frame without the crossbrace I would say no big deal. I would not risk it though if it requires removing that crossbrace with water in it unless you can get the water very low level. You would "probably" be fine, but when it comes to 150gallons of water and all my livestock on the floor I would want to be more confident than that lol

brandon429 · Apr 6, 2021

if you are going to disassemble the reef, to access it carefully, I'd like the remote job we can plan it here. removing weight from the setup before working/moving the tank is a big deal and I can tell you that draining a reef down and sloshing all that waste on refill isn't good

there is a certain way you can clean your tank, hold it parted out while you fix stand low weight, reassemble, here's a specific example/

Build Thread - Cook's 105 Planet Aquariums Crystaline Reef - 48x20

I've had my tank going for two years next month. I'm moving this build over from another forum, so the time stamps aren't going to reflect the original's. I will try to document the original dates as I go. It's also an opportunity to edit my build, there was so much at the beginning I didn't...

www.reef2reef.com

see how we cleaned it

right when yours is taken down and held in tubs is when you fix the bracing

then reassemble per skip cycle rules, not just what's most convenient. clean reassembly = skip cycle.

don't drain a used sandbed, then refill on top of it. this is considered a reset move, you are cleaning the sand to reduce the risk of recycling, skipping the rinse is the uncertain way.

wings4wheels · Apr 7, 2021

AARRGH! I was hoping that by getting the tank level down to a few inches (enough to leave the livestock in place) the pressure on the glass would be low enough to safely pop off the top and put a new one on. Sometimes I wish I was an engineer and I could calculate the outward pressure and feel confident its not going to come apart.

brandon429 · Apr 7, 2021

so its obvious I like taking people's tanks apart remotely and setting them up again, its fun

even with that slant on eval

its my honest opinion that draining down anywhere near 90% for a move or support job, or removing substrate like rocks, in a large setup like this puts a reefer on direct path for having to consider surgical means shown above because its simply the safest option, though its the most work. it seems like overdoing things, aware.

so the alternative is deep drain. move some stuff around, and refill...we have tested that before.

Sloshing refill water back over sand destratifies that sand, that's a marked change. a risk, I'm not overselling it I'm relaying it based on # of observed events.
I think if you skip accurate surgery you risk the system or most/all fish to the tune of 10%

that's 90% your favor nothing happens but you'll be getting cyano soon for a little run, that's also 90%

incidence if cyano after rip cleans? track out Cooks thread.

wings4wheels · Apr 7, 2021

Its just the top frame. I can slow pump the water back in after replacing the top frame. Definitely do not plan on moving the tank.

wings4wheels · Apr 7, 2021

So adding the water back in kills off the bacteria in the sand?

saltwaterjunkie12 · Apr 8, 2021

I did this exact same thing about 10 years ago. it was a 120 gallon AGA tank. I drained the tank about 50% of the way into a large container, removed the old frame, installed the new one and refilled the tank. Some of the corals were out of the water for several minutes but no ill affects after about a day.