I have a 1" durso drain with a 3/4" return via a PanWorld pump. The drain is rated at 890gph while the return pump is rated at 1110gph. I have a union ball valve to throttle back the return but I can't seem to find a happy medium. I have to check the sump level every day to make sure the water level doesn't get too low. I know that evaporation is contributing however I didn't think that I would need to make adjustments every 24 hrs. Could the fact that I have such a small sump also be contributing to this problem? The sump is only holding about 10-14 gallons, (total sump volume is approx 18 gallons).
drain vs return
- Thread starter Editour2
- Start date
The small size of the sump is somewhat of a problem, you'll be effected pretty quickly by evaperation which is pretty fast at this time of the year. Also, instead of throttling things back with a valve you can simply reduce the return to 1/2". A 1" drain should be able to handle any amount of water that the laws of physics will allow through that 1/2" return.
MIKE NY
Two Decade club
agree x2..... a 1" will drain aprox 600-800 gph and will decrease over time with the acumaltion of detris/calcium deposits etc.....as Bill mentioned this time of year with warm water and cooler air evaporation plays a big part too...for example on my system it evaporates aprox 4-5 gallons a day and would play havoc with the SG and water level if I didn't have a water top off system.........
If my system is evaporating even half as much as Mike's system, (I have an 85gal tank), than that in itself would account for the problem. I'm manually adding about 1 gallon every other day, (RODI water). If I were to reduce the return to 1/2" at what point would I make the reduction? My return is as follows: the sump bulk head is 1" which feeds to a 1" union ball valve leading to the pump intake. This is reduced to 3/4" after the pump. The pvc then leads to a 3/4" bulkhead for the tank. The water returns to the tank by being split into 2 - 3/4" flexible returns which feed back to the tank. Would it have the same effect if I reduced to 1/2" in the overflow section? (This would be relatively easy to accomplish, which is always the preferred method).
MIKE NY
Two Decade club
.......before re-doing all the plumbing dial back the pump alittle..I got a feeling thats it's evaporation and your not adding enough water to maintain a steady SG....your system is aprox 100 gallons and your only adding one gallon every other day....check the SG often to see if it rising.....wet skimming can also account for the loss of water......
martinphillip03
New member
Frank, you could put a T in your return line and run it back into your sump. Put a valve ( gate or ball ) on the return to the sump. You can than close the valve until you have proper flow going back into your tank
Marty
Marty
MIKE NY
Two Decade club
yes SG( Specific gravity..salinity) and if your maintaining a constant 1.024 over that 48hr period before that gallon of water without rising than your adding enough water to replace the evaporation....then if the pump is dialed back half way and your maintaining salinity than the pump is too strong and then Marty's idea will be a quick fix other than replacing the pump or plumbing ...........
Marty,
I built a T into the return line in anticipation of any problems with the drain vs return. I actually have the return divided into 3 separate areas, each with it's own ball valve: 1) back to the tank, 2) feeding a small refugium, (which is a partitioned part of the sump, the refugium drains back into the sump via a pvc overflow), and 3) returning to the main sump area. I tried running some water back into the sump however the result was that it allowed me to further open the valve feeding the return pump but it still didn't provide a constant with the sump level over time, (again dealing with the evaporation problem).
Mike,
I check the SG after I add the additional gallon of RODI water and I rarely have to make an adjustment. I never checked before I added the water, I assumed that if only water was evaporating, not salt, then the SG would rise if you did not replenish. If I added saltwater then I assumed the SG would also rise, (unless I was performing a water change).
I guess my options are: a) deal with it, b) get a less powerful pump, c) get a bigger sump, d) try changing out the 3/4" pvc for 1/2"pvc as per Bill's suggestion or e) add a top-off system.
I tried to build a system that was all inclusive, that's to say that the sump/refugium and all equipment was contained in the tank and or stand. (We'll see how long that lasts).
I don't see how the drain could ever perfectly equal the return unless both were exactly the same gph, (and you still would have to deal with evaporation unless you had an auto-top off system).
I built a T into the return line in anticipation of any problems with the drain vs return. I actually have the return divided into 3 separate areas, each with it's own ball valve: 1) back to the tank, 2) feeding a small refugium, (which is a partitioned part of the sump, the refugium drains back into the sump via a pvc overflow), and 3) returning to the main sump area. I tried running some water back into the sump however the result was that it allowed me to further open the valve feeding the return pump but it still didn't provide a constant with the sump level over time, (again dealing with the evaporation problem).
Mike,
I check the SG after I add the additional gallon of RODI water and I rarely have to make an adjustment. I never checked before I added the water, I assumed that if only water was evaporating, not salt, then the SG would rise if you did not replenish. If I added saltwater then I assumed the SG would also rise, (unless I was performing a water change).
I guess my options are: a) deal with it, b) get a less powerful pump, c) get a bigger sump, d) try changing out the 3/4" pvc for 1/2"pvc as per Bill's suggestion or e) add a top-off system.
I tried to build a system that was all inclusive, that's to say that the sump/refugium and all equipment was contained in the tank and or stand. (We'll see how long that lasts).
I don't see how the drain could ever perfectly equal the return unless both were exactly the same gph, (and you still would have to deal with evaporation unless you had an auto-top off system).
