Scott's 270g aka Project Mayhem

[reefermadness]

Don't try and use your dosing pumps to adjust the levels. You will constantly be adjusting them like a yo yo. It's much better to manually bump your parameters to the levels you want and keep the dosers set as close to maintenance you can get. You will always have a little drift but if you regularly test and bump if needed it's not a big deal.

[Scythanith]

Originally Posted by reefermadness

Don't try and use your dosing pumps to adjust the levels. You will constantly be adjusting them like a yo yo. It's much better to manually bump your parameters to the levels you want and keep the dosers set as close to maintenance you can get. You will always have a little drift but if you regularly test and bump if needed it's not a big deal.

Thanks Darryl, I will be just watching what happens for the next 3 days so that should show me a general consumption rate hopefully. One weird thing was I mixed up a 20g batch of fresh salt and it tested at 6.3 dKh. I asked Michael and he said that was normal. Seemed weird to me but he said that's the way the system worked. I googled it and saw reef builders mixed up a test batch and it tested at 8.3 dKh. Any opinions?

[Scythanith]

Well I have another little problem. I knew the bottom sump was too small after the first time I unplugged my main return pumps and the water from the display overwhelmed the bottom sump and dumped ~10g down the emergency drain. I had two power outages yesterday and each time it left my lower sump pump running half dry and emptied my ATO pail into the system. Now the ATO pail is currently only a 5g pail so it wasn't an issue but I made a promise to myself to not compromise anything in this project. So, I will need to build a larger bottom sump that can handle that extra volume. Right now the lower sump is 14 deep x 48 wide x 12 3/8 to the emergency overflow. That works out to ~36g. I need to up it to ~50g. SO I need to add ~14g of capacity. The stand itself can accomodate another 2" of sump to the front. I don't really want to go any taller and can't go any wider.

If I get a new sump made that is 5" deeper front to back that will add ~12.9g of volume which should be enough. That would also require me to build an add-on to the bottom of the sump stand to support the extra 3" of sump overhang.

Wendy suggested a sensor and pump that would start draining the lower sump when it got to a certain level and while I like that idea I know it would be fairly complex to work out not to mention the problem occurs when the power goes out so all the programming in the world isn't going to help at that moment. I honestly think a larger bottom sump is my safest & simplest solution. Any opinions or suggestions?

[FishyFishy!]

Can you run a simple check valve right after your pump? A george fischer wye check valve would be very effective and wouldn't limit flow very much.

[sphelps]

Scott did you ever try/consider cutting out the refugium to free up some extra volume in that lower sump?

[Myka]

Originally Posted by sphelps

Scott did you ever try/consider cutting out the refugium to free up some extra volume in that lower sump?

I like this idea.

[Scythanith]

Originally Posted by sphelps

Scott did you ever try/consider cutting out the refugium to free up some extra volume in that lower sump?

By my calculations that would only gain me 1.24g of volume.

[Myka]

Originally Posted by Scythanith

By my calculations that would only gain me 1.24g of volume.

Your refugium appears to be much bigger than that.

[Scythanith]

Originally Posted by FishyFishy!

Can you run a simple check valve right after your pump? A george fischer wye check valve would be very effective and wouldn't limit flow very much.

It's not backflow through the pumps, its the actual water volume from the display tank that is above the weir teeth draining into the sumps.When the top sump return pump is running, it raises the level in the main tank by ~1", the lower pump replenishes the top sump and makes up for any discrepancies in water height (usually due to evaporation). I already have a GF wye on the lower sump pump, so nothing drains back through it.

[sphelps]

I think you have a little more potential in that sump worth exploring, worst case you're replacing the sump anyway so why not try this first.

1. Add a snorkel to the pump, I've done this lots, usually use long radius ABS fitting.
2. Lower that running water level, I scaled out 3" which I think is easily feasible, maybe even more.
3. Cut out refugium, it'll add more volume to the pump chamber as well so it will have more catch up volume as well during start up.
4. Add a little height to your overflow chamber, ie if it's 12-3/8", can you make it 12-7/8"?

If you can do all that the added volume I calculate is this:

Refugium cut out and lower water level: (27*3+27*2)*13.5 = 1800 in3
Higher E-O-Flow: 0.5*47.5*13.5 = 320 in3

Total = 2120 or just over 9 gallons.

Rough numbers obviously and I didn't exclude the overflow box but you get the idea. I'd also still add a check valve to both return pumps, while it's not a total back-flow issue it will still cut back on a decent amount of water flowing back to the sump (16' of 1.25" Pipe will hold about a gallon).