finally got water in tank but....


Reefing newb
i fired up my sump and here are the problems i am having

1- the tank i have has a corner overflow, it seems to fluctuate up and down about two inches, it will fill up then suck the water this normal? my stand pipe has a 90 on the top with a hole drilled in it, i cant remember the name for the set up but im sure you all know what i mean

2-since it is sucking the water down in intervals it is really causing turbulant water flow in my sump, is this normal??

3- i was told by my LFS to go with a 900gph pump and use a ball valve to back it off, well the ball valve is practically shut to keep water in my pump compartment...its a 90 gallon tank with 1 corner overflow...1" bulkhead. Is the pump too big????

thanks in advance
getting excited
Usually you want to have your pump to at least have a return of about 5 times the water volume in one hour. It is not uncommon to see reef tanks utilize 10+ turnover rate of water volume per hour. So my guess would be that having a 900 gph pump on a 90 gal tank is not a bad thing. I don't utilize a sump so thats about as helpful as I can get. (if thats even helpful at all)
It should be a steady drain without any burping and gurgling.If it is than the pump is pumping to fast and the drain is trying to keep up.Although the drain maybe 600gph and may even handle a little more.Realisticly they are only good for 350gph or so.Mags can handle the back pressure.With it being underwater and as long as some water is being pushed through the pump there won't be any overheating.I would back it off even more.
If you're worried about putting too much back pressure on the pump, you can plumb your return line into a "T". Have one branch of the T going to the tank (with a ball valve) and have the other branch going back into the sump (with a ball valve). This reduces the back pressure on the pump by redirecting the flow back into the sump.
i had the same problem with mine ... my stand pipe has a u-pipe on top of it and a small hole drilled into the top with a small straw sticking out of it ... all i had to do to get it to quit was adjust the straw up or down to help it remove all the air from the u-pipe ... then it started siphoning properly
thanks, i backed off the ball valve a little bit and i have good flow now with no gurgling

i think i will take biffs advice and "T" off my return line and pump it back into the sump

my live rock will be showing up tomorrow, i bought 90 pounds, and it will be sitting on top of 40 pounds of live sand

should i be running my skimmer during the cycling process???????
Did your 90 gallon tank come with just one overflow drilled for a one inch bulkhead? Wow, that is not much water for a 90 gallon tank (reef readys, yuck). Reeffreak is right on at saying your proabbly getting 350 gallons per hour through your overflow. I would cut my losses and buy a new pump rated at around 450 gallons per hour. What with the head losses and friction losses of most plumbing of returns that should work out giving you about 350-375 gph at your return. The cost in savings of electricity will not quickly recoup the new pump cost quickly, but most reefers always find ways to use extra pumps and a pump used at its design capacity usually lasts much longer, and runs cooler and therefore more efficient. Yes run your skimmer asit will keep your water as oxygenated as possible. A skimmer increases your oxygen level much better than aeration or surface air to water exchanges of gases at the top off your tank.
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thanks fatman

yes my tank came with 1 overflow

what makes me a little mad is the LFS suggested i go with the bigger pump, insisting that my overflow would drain 700 to 800 gph

furthermore my LFS is "that fish place" in lancaster PA, i figured they knew what they were talking about

one of the engineers where i work did the math and came up with +/- 400gph for a 1" overflow

the pump i had originally bought was rated at 600gph but with the head height would hve achieved about 350 to 400

i think i will just get the smaller pump

now at 350 to 400 gph i would only be turning my tank about 4 times an hour
how many powerheads will i need to make up for that?????
People seem to think you need massive gallons of water go through a don't and it's usually never enough for decent amount of flow.I recommend two or three Koralia model 3 for added flow.The return pump could always be use to split the flow back to the tank and a separate refugium later on if you so choose.
Aim for around 10 times the volume of your tank in flow. So if you are at 4 times with the sump, then make up the other six (at least) in powerheads. Keep in mind, 10 times is a good, basic number for most coral types. If you want to keep SPS, you will need higher flow.
I dril holes, lots and lots of holes. Fill them with all kinds of plumbing and supply massive circulation. Really there are all kinds of appraches to providing circulation. Research the subject and you will find subjects such as closed loop circulation, over the back returns and power heads. Power head sare the easy way, but fortunatly one of the the most obtrusive way to provide circulation. Your lucky to have an engineer at your disposal. The rating of 350 to 400 gph is the accepted general average rating given by engineers and the experts in the marine reef industry for a one inch bulkhead with a one inch piece of PVC pipe in it. "Reef ready" overflow towers are the most obtrusive method. For more information and opinions on the subject than any one could ever need look up at the following URL, in the marine tank section, tank set up, "circulation" at